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Full text of "System of diseases of the eye. Vol. 4, Motor apparatus, cornea, lens, refraction, medical ophthalmology"

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of the 


of optometry 



45 Druttl Bfrultwcl 







A V 



1900 . 


it th» 



Copyright, 1899, 


J. B. Lippi SCOTT Company. 

(5 s 




mZ , F ^ Pard library 

of Optometry 
3241 Michigan Ave 

Chfttgo, Ml. 60616 , q 3.$ 

Electrotyped and Printed by J. B. Lippincott Company, Philadelphia, U.S. A. 


EDMUND LANDOLT, M.D. Paris, France. 

J. P. NUEL, M.D. . . .. Liege, Belgium. 

WILLIAM U- NORRIS, A.M., M.D. Philadelphia, Pa , U.S.A. 

CHARLES A. OLIVER, A.M., M.D. Philadelphia, Pa., U.S.A. 

O. HAAB, M.D. Zurich, Switzerland. 

HENRY R. SWANZY, A.M., M.B., F.R.C.S.I. . Dublin, Ireland. 

J. B. LAWFORD, M.D., F.R.C.S. (Eng.) .... London, England. 

JOHN B. STORY, M.B., F.R.C.S.I. Dublin, Ireland. 

J. SANTOS-FERNANDEZ, M.D. Havana, Cuba. 

M. PARINAUD, M.D.. Paris, France. 

JONATHAN HUTCHINSON, Jr., F.R.C.S. . . London, England. 

MYLES STANDISH, A.M., M.D. Boston, Mass., U.S.A. 

GEORGE E. de SCHWEINITZ, A.M., M.D. . . Philadelphia, Pa., U.S.A. 


S. BAUDRY, M.D. Lille, France. 

A. GAYET, M.D. Lyons, France. 


_ ^ 

C. M. CULVER, A.M., M.D. ^^^X>any, New York, U.S.A. 

THOMAS H. FENTON, M.D. Sr ^Philadelphia, Pa , U.S.A. 

WILLIAM ZENTMAYER, M.D.• Philadelphia, Pa., U.S.A. 

CASEY A. WOOD, C.M., M.D. . . .... Chicago, Illinois, U.S.A. 

H. V. WURDEMANN, M.D. . . Milwaukee, Wis., U.S.A. 

FRANK W. MARLOW, JVUQ:, M^R.C.S.E. . . . Syracuse, New York, U.S.A. 
EDWARD C. ELLETT, M.%J^. Memphis, Tenn., U.S.A. 





Edmund Landolt, M.D., of Paris, France, translated by C. W. Culver, 
A.M., M.D., Ophthalmic Surgeon to the Albany Orphan Asylum, Albany, 

New York, U.S.A. 3 

DISEASES OF THE CORNEA. By J. P. Nukl, M.D., Professor of Oph¬ 
thalmology in the University of Liege, Liege, Belgium. Translated by Thomas 
H. Fenton, M.D., Medical Director and Senior Ophthalmic Surgeon to the 
Union Mission Hospital, Philadelphia, Pennsylvania, U.S.A.169 

DISEASES OF THE LENS. By William F. Norris, A.M., M.D., Pro¬ 
fessor of Ophthalmology in the University of Pennsylvania, and one of the 
Attending Surgeons to the Wills Eye Hospital.. 257 


Charles A. Oliver, A.M., M.D., Attending Surgeon to the Wi^XEye Hos¬ 
pital; Ophthalmic Surgeon to the Philadelphia Hospital, Philte^jdlia, Penn¬ 
sylvania, U.S.A. .J2T. . 401 

CULATORY SYSTEM. By O. Haab, M.D., ProfjJ0^ of Ophthalmology 
in the University of Zurich, Zurich, Switzerlandv-vK^anslated by William 
Zentmayer, M.D., Assistant Surgeon to Wills Eye Hospital; Ophthalmic 
Surgeon to St. Mary’s Hospital, Philadelphia. Pennsylvania, U.S.A.481 


By Henry R. Swanzy, A.M., M.RVpfe.C.S.I., Surgeon to the Royal Vic¬ 
toria Eye and Ear Hospital, and Qfi^th^mic Surgeon to the Adelaide Hospital, 
Dublin, Ireland.*.539 

M.D., F.R.C.S. (Eiw.£Dplithalmic Surgeon to St. Thomas’s Hospital, London; 
Surgeon to the RoyjfW^5ndon Ophthalmic Hospital, Moorfields, London, Eng¬ 
land . . . . 645 

M.B., JjAc.S.I., Surgeon to the Royal Victoria Eye and Ear Hospital; Ex- 
anuneCX Ophthalmic and Aural Surgery in the Royal College of Surgeons, 
Drain, Ireland.687 





Santos-Fernandez, M.D., Director of the Histo-Bacteriological Laboratory 
of the Cronica Medico-Quirurgica, Havana, Cuba. Translated by Lieutenant 
Daniel M. Guiteras, M.D., Passed Assistant Surgeon, United States Navy . 705 

M.D., Senior Chief of the Ophthalmological Service of the Salpetriere Hospital, 
Paris, France. Translated by Casey A. Wood, C.M., M.D., Professor of 
Ophthalmology in the Post-Graduate Medical School, Chicago; Ophthalmic 
Surgeon to the Cook County Hospital, Chicago, Illinois, U.S.A.727 

ZOSTER. By Jonathan Hutchinson, Jr., F.R.C.S., Surgeon to the London 
Hospital; late Ophthalmic Surgeon to the Great Northern Hospital, London, 


Ophthalmic Surgeon to the Massachusetts Charitable Eye and Ear Infirmary; 
Assistant to the Chair of Ophthalmology in Harvard University, Boston, 
Massachusetts, U.S.A.781 

THE TOXIC AMBLYOPIAS. By George E. de Schweinitz, A.M., MD., 
Professor of Ophthalmology in the Jefferson Medical College; Ophthalmic 
Surgeon to the Philadelphia Hospital, Philadelphia, Pennsylvania, U.S.A. . . 797 

THE ENTOZOA OF THE HUMAN EYE. By Maximilian Salzmann, 
M.D., Docent for Ophthalmology at the University of Vienna, Vienna, Austria. 
Translated by H. V. Wiedemann, M.D., Lecturer on Eye and Ear Diseases to 
the Elms Hospital and Training School, and Milwaukee County Hospital, Mil¬ 
waukee, Wisconsin, U.S.A. 843 

SIMULATED BLINDNESS. By S. Baudry, M.D., Profe^^in the Faculty 
of Medicine in the University of Lille; Ophthalmic Sur^gOnt$ the Board of 
Charities of Lille, Lille, France. Translated by Fran^W. Marlow, M.D., 
M.R.C.S.E., Professor of Ophthalmology in the Department of the 

University of Syracuse ; Ophthalmologist to the Ne^fork State Institution for 
Feeble-Minded Children at Syracuse, Syracuse Xk* fork, U.S.A.861 

THE OCULAR SIGNS OF DEATH. ^v^<Gayet, M.D., Ex-Surgeon-in- 

Ophthalmology to the 
i’rance. Translated by 




Dissimilar figures of truncated pyramid. 

Corresponding points on fusion pictures. 

Figure illustrating position of miner while at work. 

Figure illustrating position of miner while at work. 

Figure illustrating position of miner while at work. 

Hyaline degeneration of the parenchyma of the cornea. 

Primary degeneration of the corneal epithelium in the form of inflammation occur¬ 
ring in band-shaped affection of the cornea. 

Profile view of keratoconus .. 

Primary epithelioma of the cornea. 

Subconjunctival dislocation of the lens with subsequent cataractous degeneration . . 
Subconjunctival dislocation of the lens with subsequent cataractous degeneration . . 

Lens spectrum. 

Volume of lens. 

Section of senile cataract .. 

Spindle-shaped spaces between lens-fibres filled with molecular material. 

Cataractous degeneration of lens-fibres. 

Cataractous degeneration of lens-fibres. 

Cataractous degeneration of lens (near the vertex).\. 

Gelatiniform degeneration of lens-fibres beneath a posterior synechia^^A. .... 

Spindle-shaped masses with striation transverse to length of spindli^\^. 

Proliferation of capsular epithelium in an overripe cataract . . 

Marked epithelial proliferation in intact capsule.. 

Marked epithelial proliferation in intact capsule.Vv*/. 

Traumatic cataract in process of absorption .... ..<^N. 

Traumatic cataract in process of absorption . ... C . 

Traumatic cataract in process of absorption . . 7^ . 

Traumatic cataract in process of absorption . . . 

Effects of a discission operation. 7 ^. . 

Effects of a discission operation .... .. 

Two perforations in a lens from a discisajSi^peration ... . 

Cap of fibrinous and spindle cells cfc^r&g the wound made by a discission needle . 

Proliferation of cells in capsule^if/e\OTtraction. ...... 

Normal appearance of capsulaandenclosed lens remnants after a successful flap op¬ 
eration for cataract . . ^ . 

Cataract following tumor 4 ^r^e chorioid with detachment of the retina, the greatest 

changes being near^^anterior capsule. 

Leucocytes hetwe^i^^iens-fihres in a case of traumatic cataract. 

Leucocytes bet\^mjhe lens-fibres in a case of traumatic cataract, more highly mag¬ 
nified . . . 

Effects ofjllMge on the human lens. 

Upper Lal^ff extraction-cicatrix nine weeks old. 

LowerffiS^f of extraction-cicatrix nine weeks old. 































Displacement of lips of the wound with cystoid cicatrix. 

Cicatrix after sclerotomy... 

Cicatrix nine weeks old . 

Section of zonular cataract. 

Section of a zonular cataract, showing equator of the zonule. 

Section of a zonular cataract, showing equator of the zonule, more highly magni¬ 
fied . 

Secondary cataract after extraction with iridectomy. 

Secondary cataract after extraction with iridectomy.. 

Secondary cataract after extraction with iridectomy. 

Secondary cataract after extraction with iridectomy... 

Secondary cataract after simple extraction . 

Cystoid cicatrix in glaucoma after cataract operation. 

Anaemia of the central retinal artery and its branches. 

Ophthalmoscopic appearances in pernicious anaemia. 

Microscopic section of the retina in the vicinity of the papilla. 

Microscopic section of the retina farther away from the papilla. 

Microscopic section of retinal hemorrhages in pernicious anaemia. 

Thrombosis of branch of the central retinal vein. 

Pronounced thrombosis of the central retinal vein. . 

Syphilitic endarteritis of the retina. 

Relapsing retinal hemorrhages in young persons. 

Disease in the region of the yellow spot in each eye in an infant. 

Appearances of Mr. Power’s case of congenital deformity of the skull during life . 
Appearances of interior of cranium in Mr. Power’s case of congenital deformity of 

the skull... 

Albuminuric retinitis... 

Albuminuric retinitis. 

Albuminuric retinitis. 

Albuminuric neuro-retinitis. 

Microscopic section of albuminuric retinitis. 

Microscopic section of albuminuric retinitis, more highly magnifi 
Retinitis in glycosuria. 

Longitudinal section of the posterior half of the right bulbu^Ift^Tfive millimetres of 

the optic nerve.. J 

Transverse section of the right nerve eight millimetres the globe. 

Transverse section of the nerve thirteen millimetrasA^Hncl the globe. 

Transverse section of the nerve in the region of me <|ptSc foramen. 

Transverse section of the nerve in the region tn?Tnptic nerve. 

Transverse section of the nerve in the intraeffltoVil region. 

Longitudinal section of the posterior haRA>fTtie left bulbus and eight millimetres of 

the optic nerve.. 

Transverse section of the left nerv^Aj^illimetres behind the globe. 

Transverse sections of the nervq^AjP neighborhood of the optic foramen. 

Transverse section of the right^yive just in advance of the chiasm. 

Transverse sections of the/jEi^m and right optic tract. 

Section of normal optic ntfks&rof dog.. 

Transverse section of nerve of dog blind one month from quinine. 

Transverse section fl^y^uc nerve of dog blind sixty-two days from quinine .... 
Ganglion cell^inrti^ftn'ent stages of degeneration, third day of quinine poisoning . . 
Almost con^A^absence of ganglion cells and nerves-fibres, sixth week of quinine 


A recentlV immigrated cysticercus. 

Sam^/ISwSfyvious figure, eight days later. 

^sticercus, with well-developed head.. .. 

Jteercus free in the vitreous humor... 





















































Normal field of fixation of a right eye. 4 

Convergent strabismus of the left eye due to paralysis of the external rectus muscle . 6 

Divergent strabismus of the left eye due to paralysis of the internal rectus muscle. . 7 

Diagram explaining strabismus. 9 

Direction of inclination. 10 

Diagram illustrating paralysis of the left external rectus muscle. 12 

Diagram illustrating the movement of the head to obtain single vision with the two 

eyes in paralysis of the left external rectus muscle. 13 

Diagram illustrating diplopia of paresis of the left external rectus muscle. 15 

Diagram illustrating diplopia of paresis of the right external rectus muscle. 15 

Diagrams illustrating excursions of eyes. 16 

Diagram illustrating anatomy and physiology of the extra-ocular muscles ..... 21 

Relative position of the double images in paralysis of the external rectus muscle of 

the left eye..•. 22 

Relative position of the double images in paralysis of the external rectus muscle of 

the right eye. 22 

Field of fixation of a left eye affected with paresis of the external rectus muscle . . 
Relative position of the double images in paralysis of the internal rectus muscle of 

the left eye.• • . . . 

Relative position of the double images in paralysis of the internal rectus muscle of 

the right eye. 23 

Fixation-field of a left eye affected with paresis of the superior rectus muscle .... 23 

Relative positions of the double images in paralysis of the superior rectus muscle of 

the left eye. 24 

Relative positions of the double images in paralysis of the superior rectus muscle of 

the right eye. 24 

Relative positions of the double images in paralysis of the inferior rectus muscle of 

the left eye. 25 

Relative positions of the double images in paralysis of the inferior rectos muscle of 

the right eye.yOj. 25 

Right eye seen from temporal side. 26 

Position of the double images in paralysis of the inferior obliotfb^rrii; 

eye.-5^ • 

Position of the double images in paralysis of the inferior iQfccpie muscle of the right 

eye. 2 ? 

Fixation-field of a right eye affected with paresis oftha superior oblique muscle . . 28 

Position of the double images in paralysis of th&up^rior oblique muscle of the left 

eye. 28 

Position of the double images in paralysis o&thesuperior oblique muscle of the right 

eye . .. 28 

Fixation-field of a right eye having na^sisr^f the common motor oculi. 29 

Fixation-field of a right eye havi^S^sfresis of the common motor oculi more ad¬ 
vanced than that of the m&vlp\rfigure. 29 

Field of fixation of a right eCejlnected with paresis of the oculo-motorius and the 

abducens. 30 

Fixation-fields of both JftfePof the same person afiected by double paralysis of the 

third and the sixtfl^Jirs. 31 

Landolt’s ophth^fn^fcrcpe. Right eye under the influence of the superior oblique 

muscle . ^3 

Scheme of th« right eye. 35 

DiagramJiHfewating position of images. 40 

Object^e swbometry. 45 

rfuscle of the left 



^illustrating angle Kappa . 46 



Action of prism on eye. 

Normal binocular field of fixation. 

Field of binocular vision before advancement of tbe inferior rectus muscle . . . . 

Field of binocular vision after advancement of the inferior rectus muscle. 

Fields of fixation of a person affected with a high degree of convergent concomitant 

strabismus of tbe left eye .. 

Wheatstone’s fusion pictures. 

Wheatstone’s mirror-stereoscope. 

Javal’s stereoscope with five movements. 

Holmes’s stereoscope.. 

Oliver’s stereoscope. 

Landolt’s stereoscope. 

Left eye with convergent strabismus of thirty degrees. 

Left eye after setting back of the internal rectus muscle. 

Left eye after advancement of the external rectus muscle. 

Landolt’s forceps. 

Fields of fixation of two strongly myopic eyes affected with divergent strabismus . . 

Diagram illustrating measuring of convergence. 

Amplitude of convergence. 

Landolt’s ophthalmodyanometer. 

Herschel’s double prism with Landolt’s divisions. 

Landolt’s kinophthalmoscope. 

Abducting power of prisms. 

Effect of decentration of concave spherical lenses. 

Effect of decentration of convex spherical lenses. 

Effect of tenotomy on amplitude of convergence .. 

Effect of advancement on amplitude of convergence. 

Vertical incision of the cornea. 

Provisional occlusion of a corneal perforation (of a rabbit) by a plug of fibrin 
Provisional occlusion of a perforating wound of the cornea (of a rabbit\dating some 

eight hours. 

Cicatrized ulcer of the cornea.. 

Superficial infiltration of the cornea, producing a projectior^Klfe surface of the 


Infiltrated corneal ulcer.. 

Subepithelial cellular infiltration in a vesicle of phlycfeei§Jir ke 

Granular pannus of the cornea. 

Epithelial excrescence in filamentary keratitis 
Longitudinal section of a macula in superficiaj^inctate keratitis 
Bullous keratitis.. 

Large cicatrix of the cornea, with thin and with adhesions to the iris .... 

Corneal ulcer with hypopyon (ulcus . 

Parenchymatous keratitis .... yVfj).. 

Hutchinson’s teeth, occurring in^qgSnital syphilis. 

Precipitation-of lead on the . 

Corneal staphyloma of a ntoretor less conical shape 
Buphthalmos in consequ£nc^m a corneal ulcer acquired in infancy 

Fistula of the cornea*<^jJ. 

Keratoscopic image^rj^ case of keratoconus. 

Insertion of susn^^ry ligament into lens capsule. 

Double im^&^^£ eye-ground seen by use of concave mirror and condensing lens in 
an eye w^ ectopia lentis , 

Six case* 

Dislo^tecl H ns caught between the lips of the scleral wound 

D&jwaHon of lens between the sclerotic and the outer surface of the iris and the 
^^eiliary body. 


d 5 

keratitis , 

eye ectopia lentis. 

e^Jf ectopia lentis occurring in one family , 
ted llms caught between the lips of the scler 




































Horseshoe-shaped notch in the posterior surface of the lens. 

Ectopia of both lenses, with coloboma of each lens and of the zone of Zinn . . . . 

Coloboma of right and of left lens. 

Kidney-shaped lens ; coloboma inward. 

Perinuclear opacity in each lens, with lateral coloboma of the left; coloboma of the 

iris in both.. 

Lenticonus anterior. 

Lenticonus in pig’s eye. 

Lenticonus in rabbit’s eye. . . . . 

Softening and deformity of lens in suppurative panophthalmitis. 

Flattening of the lens in case of staphyloma of the cornea. 

Deformity of lens caused by pressure of an intra-ocular tumor. 

Distorted lens. 

Hernia of the lens with intact capsule... 

Growth of lens between the ages of twenty-five and sixty-five. 

Sectors of lens cloudy with transparent intersectorial lines. 

Opacities in forming cataract.. 

c dR 




Nucleated and swollen lens-fibres, “ alga-like” formations in the interfibrillar spaces 

Section of Morgagnian cataract.. 

Partial capsular and lenticular cataracts caused by retained pupillary membrane . . 

Capsular complicate cataract.. 

Capsular cataract caused by pressure of a granuloma of the iris.. 

Acquired anterior central capsular cataract. 

Acquired anterior central capsular cataract. 

Subcapsular spindle-cells resembling fibrous tissue. 

Capsular rents after simple extraction. 

Folds of Descemet’s membrane in striated keratitis. 

Folds of Descemet’s membrane in striated keratitis. 

Cicatrix after cataract operation ; riding up of peripheral lip of wound. 

Triple zonular cataract. 

Axial cataract. 

Congenital anterior polar cataract in a case of conical cornea .... .... 

Some forms of zonular cataract . . . . . 

Zonular cataract.Gy. 

Triple and double zonular cataract. 

Zonular cataract with curved projections into the clear lens. 

Zonular cataract with clear central axis . . . 

Irregular and malformed teeth in a case of zonular ca 

Stellar cataract. V 

Punctate and stellar cataract.. 

Punctate and stellar cataract in a case of aniridiiQ. 

Equatorial striae of a young myope which cl^cd entirely in five years’ time . . . 
Stellar posterior cortical cataract which renamed stationary for twelve years’ time . 

Traumatic rupture of the posterior . 

Secondary cataract after extraction iridectomy. 

Secondary cataract after extractifTn^/th iridectomy. 

Secondary cataract after extraction/with iridectomy. 

Diagram illustrating visual ^diasia. 

Diagram illustrating comA^te deviation. 

Narrowing of the visuaAfi/lds for white and colors in hysteria. 

Visual field in hyste\S%l dyschromatopsia . . . .'. 

Reversal of visut^^lds in hysteria. 

Diagram illustfeiting the connection between the eighth and the sixth cranial nerves . 

Fine-point^^Aptomy forceps. 

Narrov\noirated tenotomy scissors. 

Slendgm^otomy hook. 






























Visual fields in alcohol-amblyopia.799 

Unusual type of visual fields in alcohol-amblyopia.800 

Unusual type of visual fields in alcohol-amblyopia.800 

Visual fields from a case of progressive scotomatous optic-nerve atrophy of toxic 


Average papillo-macular scotoma.805 

Typical scotoma for red and green.806 

Small scotoma confined to fixation-point often overlooked.806 

Breaking through of the scotoma.807 

Absolute defects within relative scotoma.- . ...807 

Visual fields in alcohol-tobacco amblyopia.810 

Transverse section of the optic nerve in toxic retrobulbar neuritis.814 

Portion of diseased area in toxic retrobulbar neuritis...815 

Visual fields in amblyopia from bisulphide of carbon poisoning.819 

Central scotomas from lead-amblyopia with peripheral contraction of the visual field 825 

Visual fields in H. H. Harlan’s case of quinine-blindness after fifty days.833 

Diagram illustrating Baudry’s apparatus for the detection of simulated blindness . . 879 

Diagram illustrating Z. Lawrence’s test with the stereoscope.882 

Diagram illustrating the intercrossing test with the stereoscope.883 


ZP-A-K/T I"V\ 






Paris, France. 


C. M. CULVER, A.M., M.D., 

Ophthalmic Surgeon to the Albany Orphan Asylum, Albany, New York, U.S.A. 


In the study of this subject, we must keep in mind the origin and in¬ 
sertion of the muscle, as well as its plane of action, which passes through 
these two points and the centre of rotation of the eye. 1 If we recall the 
fact that the muscle by its contraction brings its points of insertion and 
origin towards each other, we shall know not only the influence which the 
muscle exercises on the eyeball under normal conditions, but also the symp¬ 
toms which result from its paralysis. aA 

General Symptomatology .—The first consequence of para^^s of a muscle 
of the eye is a diminution of the rotation of the globeJl^nie direction in 
which the muscle normally causes the eyeball to turiy^N^ 

The limitation of the field of fixation, 2 thu&^&auced, is more pro¬ 
nounced in proportion to the completeness o/T^h^paralysis, and is more 
characteristic in proportion as the muscle ii^qu^tion is the only one to act 
in a certain direction. Thus the rotations(a}jound the vertical axis towards 
the temple and the nose are accomplishq^fodmost exclusively by the external 
and internal recti muscles. Hence uj03ysis of the external rectus muscle 
almost entirely annihilates the i^K8«fction of the eye and produces a con¬ 
siderable gap in the temporaLs^of the field of fixation. 

The same is not absolAt£$ the case for the superior and inferior recti 

1 In the case of the supA^roblique, the pulley through which it passes must be con¬ 
sidered as its origin. 

2 By field of we understand the space which an eye dominates by its move¬ 

ments, or the aggr^^fejHn of all the points in space towards which the line of sight of an 
eye may he directed while the head remains motionless. The limits of the fixation-field 
correspond, to the limits of the excursions of the eye. They extend, in all 

directions VfboSir forty-seven degrees. See Fig. 1, which represents the minimum field of 
fixatioiu^yfcight eye. Here the field is limited much within and below by the nose. 

M 3 



Fig. 1. 

Normal field of fixation of a right eye. 

and oblique muscles, because their action is almost always a combined one. 
For rotation about the transverse axis, for instance,—the raising and lower¬ 
ing of the e\ e, at least two muscles act together. Looking downward is 
accomplished by the combined action of the inferior rectus and the superior 

oblique muscle; looking upward, by 
that of the superior rectus and the in¬ 
ferior oblique. 

If there be paresis or even paralysis 
of one of the depressors,—of the su¬ 
perior oblique, for instance,—a lessen¬ 
ing in extent of the lower part of the 
field of fixation will be discoverable; 
but this lack of action will never be so 
great as that on the temporal side pro¬ 
duced by paralysis of the.abductor, be¬ 
cause the inferior rectus muscle has 
also to do with looking downward. 
It is true that, by its own action, the 
superior oblique muscle causes the eye 
to turn not only downward, but also 
outward. Hence, when the superior oblique muscle is paralyzed, we ought 
to find a defect at the lower and outer sides of the field of fixation. Such 
a diminution is to be found (see Fig. 19), but only in very pronounced 
cases; for the external rectus, by combining its action with that of the 
inferior rectus, can to a certain degree furnish an equivalent of the abducent 
action of the superior oblique. 

In case of paralysis of the superior oblique nvnttte, there is a third rota¬ 
tion which the other muscles would not so raffixTy succeed in producing; 
this is the rotation around the antero-post^V axis, the inclination of the 
meridians of the eye. It is not shown ioH&Se field of fixation, which marks 
only the excursions of the line of ^T^jp^but does not indicate rotations 
around this line. In order to denJon^Crate a pathological inclination of the 
meridians of the eye, it is necess^j^ to have recourse, as Donders lias pro¬ 
posed, to accidental images. we know that the superior oblique, while 

causing the eye to turn doJ^Ward and outward, exerts upon it a rotation 
about the antero-post$K«yixis, which causes the upper end of its vertical 
meridian to lean tojy^rlj^ the nose. The opposite occurs through the influ¬ 
ence of the inferi<j^ctus, which inclines that meridian outward. Under 
normal circumfences these two influences counterbalance, so that when 
merely look^JtfVdowmvard, the eye executes no rotation of this sort, its 
verticaUj^Ncban, for instance, remaining vertical. Withdrawn, however, 
from <ffi^Sfction of the superior oblique and abandoned to that of the in¬ 
ferior i>ctus, the globe will undergo the rotation which the latter tends to 
Sytjupon it; its vertical meridian will lean towards the temple. Tin’s 

inclination will manifest itself directly by the accidental image of a vertical 



line. Let the diseased eye be made to fix upon a red ribbon that is stretched 
vertically across a white background. After a minute, let the eye look 
downward, then the accidental (green) image of the ribbon will appear on 
the background no longer vertical, as would be the case if the experiment 
were made with a normal eye, but inclined towards the temple when there 
is paralysis of the superior oblique muscle, and towards the nose when it is 
the inferior rectus that is paralyzed. 

It is true that the experiment with the accidental image requires, on 
the patient’s part, intelligence and ability to observe correctly, upon which 
we cannot always depend in practice. It is, however, in connection with 
an examination of the field of excursions and some other symptoms with 
which we shall become acquainted, a most welcome aid when an exact 
diagnosis without the collaboration of the other eye is to be made. 

The diagnosis of paralysis of an ocular muscle is much easier when the 
fellow-eye is normal. In such a case, when the patient’s attention is 
directed to a distant point, only the better eye will be directed towards that 
point and kept in that direction by the equilibrium of its muscles. On 
the contrary, the diseased eye will be abandoned to the traction of the 
antagonist or antagonists of the paralyzed muscle. They exercise a pre¬ 
ponderant action upon the eyeball, and cause its line of sight to deviate 
in a direction opposite to that in which the affected muscle would have 
moved it. 1 Such a deviation is called strabismus,—paralytic strabismus 
in this case, in which the condition is due to paralysis of a muscle of 
the eye. 

As an example of this let us take the paralysis of the external rectus . 
Under normal circumstances, this muscle turns the eye to\m^ls the temple. 
Deprived of its action, the eye deviates towards the nos< 

Let 0 (Fig. 2) be a point infinitely distant, so thawA order to fix the 
eyes upon it, they ought to be directed parallelly fiAyhrd. In the case of 
paralysis of the external rectus of the left eye, A^4ye undergoes rotation 

1 It is important to bear in mind that the anttfgo^^of an ocular muscle is not simply 

the muscle which causes the eyeball to turn atere^the same axis, but is the aggregate of 
the motor forces which act as opponents. OnhM external and internal recti can be re¬ 
garded as pure antagonists, so that, if oimKlhem is paralyzed, the eye’s direction and 
position are the same as if the other hatL^onfracted. But even in such a case the other 
muscles, which act in the same sens^\jfey tfTeir influence to that of the antagonist.—The 
superior and inferior recti are ncdrwwagonists any more than are the two obliques, in 
the sense that, withdrawn fro/i tff^action of one of them, the eye would behave as if it 
were abandoned to the other mus^Te of the same pair. For example, the superior oblique 
turns the eye downward outward, and inclines the vertical meridian towards the 
median plane. Its so^y^d antagonist, the inferior oblique, turns the eye around the 
same axis, in the opn^^way,—that is to say, upward and outward,—exerting a temporal 
inclination upoj^tSjQ^rtieal meridian. The real antagonists of the superior oblique (those 
to which the ey^ftbmits in case it is paralyzed) cause the eye to turn upward and in¬ 
ward, wliile^ey incline the vertical meridian towards the temple. This law, which 
results fr&m simple reflection, is confirmed by observation, as will be seen in another 



around its centre of motility (m) towards the nose; its visual line, instead 
of being directed towards 0, will be directed towards &. 1 It will form, 

Fig. 2 . 

0 ' 








\ / 



\ I 



' j 


\ / 




\ j 






\ / 


\ / 


\ / 

\ / 

\ / 






\ / 

\ / 

\ / 






/ \ 

/ \ 


/ \ 


/ \ 



/ \ 


/ \ 



/ \ 

/ \ 

f \ 

l L 

" ) ( <R ) 

\ J \ ' J 



Convergent strabismus of the left eye due to paralysis of the ext* 

•ectus muscle. 


with the direction that it ought to have, the angle which is called the 

angle of strabismus . 2 

The visual line of the diseased eye will^@mat of the normal eye on 
the proximate side of the fixation-object£Tfte two visual lines converge, 
whence the name convergent strabismus p given to that form of deviation 
of the eye. 3 

1 We do not ignore the fact thab-4he"optic axes, with reference to which the retinal 

images are projected, do not cross aMfe^centre of motility, hut in the optical centre, or in 
the nodal points of the eye. (g^^mdolt, The Refraction and Accommodation of the 
Eye, pp. 86 and 121.) For of simplicity, we may he permitted to considey these 

points as fused in one. Xh^jshltant error has no effect on the practical questions which 
are now being treated. ^F(Jf the same reason the visual line and the line of sight may he 
considered identical^hough they are really distinct. (Landolt, loc. cit., p. 117.) 

2 Landolt, GnO^Omd Saemisch, iii. S. 325, 1874; Landolt, Manual of Examination 
of the Eyes, p. )e Wecker et Landolt, Traite complet, i. p. 909. 

3 It wjM^fejVoticed that we have supposed the fixation-point 0 to he at an infinite dis¬ 
tance. case, the visual line of the right eye is parallel with the direction oO, that 

the lefteylSought to have. Again, the distance of the fixation-object being infinite, the few 
centjm^es between the two eyes may be disregarded with reference to it, and we may 
^on^jfcr'the two eyes as fused into one. In this case, the line oO coincides with the line 

!, as in Fig. 4, in which we have supposed the two eyes to be superposed in profile. 



In the case of paralysis of the internal rectus muscle, whose normal 
function is to direct the eye towards the nose, there will be an opposite 
deviation,—towards the temple, OmQ (Fig. 3),— divergent strabismus, rela¬ 
tively to the other eye. 

Fig. 3. 

O O' 

o' Ff ? JS> 

Divergent strabismus of the left eye due to paralysis of the internan^^is muscle. 

The action of the superior oblique is to turH eye downward and 
outward, and to produce, moreover, a rotatiomsffSuhd the antero-posterior 
axis in such a way as to incline the vertical \jie/iman towards the median 
plane. In paralysis, therefore, of the smgrior oblique, the eye will be 
turned upward and inward, and its vertical meridian will lean towards the 
temple,— strabismus sursum vergens^Mwe, rgent and temporal inclination. 

Pathological deviation of the ^^q}roduces another of the most charac¬ 
teristic symptoms of muscular p^aiysis, at least when binocular vision has 
been present. This is doiriSTeNnsion, or diplopia . 

The explanation of^hiSr phenomenon is most simple. 1 Let us again 
take the example of^m^flysis of the external rectus of the left eye, and 

1 This expla^^^cTf diplopia, with a descriptive figure, we have given in Ann. d’ocu- 
listique for 187fi,lS^Kin our Manual of the Examination of the Eyes, p. 63, 1879. It is 
also spoken o^^ p. 822 in vol. iii. of the Traite complet d’Ophfhalmologie of De "Wecker 
and LandoiC ; Nevertheless the authors of manuals continue to copy from each other a 
totally (^mwieous figure, which fact serves well to show how greatly this simple phenomenon 
is stilrtySunderstood. 



suppose that the individual’s attention is directed upon the point 0, Fig. 2. 
The normal eye (R) only will be directed towards this point, so that the 
image of 0 will be formed upon its fovea centralis, <p. 

In the left eye (Z), on the contrary, this eye being deviated towards £, 
the image of 0, instead of being formed on the fovea centralis,/, will fall 
on the point o, at the inner, nasal side of the fovea. 

Without taking into account the wrong direction of the left eye, the 
individual projects this image—that is to say, he supposes the object that 
has caused it to be—at the place where an object ought to be in order that 
its image, in the normal direction of this eye, will be formed at o. 

To know where the patient sees the object 0 , we.need, therefore, only 
to cause the left eye to take its normal direction; in other words, to place 
its fovea centralis opposite the point 0, The point / will then be where 
o was before, and o will have passed along to o'. Let a straight line be 
drawn from o' through m to the plane in which is the object 0 (and in 
which the patient usually projects the false image), and we shall find at 0 ' 
the place where the object 0 appears to be to the deviating eye. 

We see that the false image, as we may call it, is at the opposite side 
from the deviation,—that is to say, at the side towards which the paralyzed 
muscle would normally direct the eye. 

Speaking with relation to the sides of the body, we may say that, in the 
paralysis of an abductor, the false image appears at the side of the affected 
eye; at the left, in the example taken, since the external rectus of the left 
eye turns that eye towards the left. 

If the image as seen by the left eye is at the left, and that belong¬ 
ing to the right eye is at the right, the diplopis^^^illed homonymous. 
Tliis characterizes convergent strabismus. Qj 

The same thing occurs in the case of pa^^is of the internal rectus 
muscle of the left eye. For instance, in the eye is deflected outward 

(fmfy. The image of 0 is produced a^y^Restoring the normal direc¬ 
tion to the eye, o goes towards o', an^)'designates the place at which the 
paralyzed eye sees the object 0. J&ain, it supposes the image to be in the 
direction opposite to that of the ^Sbismus,—that is to say, in the direction 
in which the affected muscle act if not paralyzed. 

At the same time, that, in such a case of deviation towards 

the affected side, the fate^jliage ( O') is at the side of the sound eye. Since 
this sound eye see^th Object in its real position 0, the double images are 
crossed, that of thsU<?ft eye being at the right and that of the right eye 
being at the l£^. Thus, crossed diplopia shows divergent strabismus, just 
as homonyi liplopia expresses convergent strabismus. 

AnAjW^iis reasoning gives us the position of the false image in the case 
of dev^wn in the vertical direction. 

Fig. 4 the two eyes are supposed to be superimposed in profile. The 
no^nai ey 


. eye (dotted) is directed straight forward towards an object 0, whose 
linage is formed at the fovea centralis <p. The diseased eye (plain line) 



inclines upward towards £2 (strabismus sursum vergens). The diseased 
eye receives the image of 0 at a point o above its macula. Normally, 
this point would have been struck by rays coming from below the 

Indeed, if we turn this eye back to its normal direction, so that its 

Fig. 4. 

and the line 
as the visual 

fovea centralis is opposite 0 , o will take the position of 
o'mO' will give at O' the false image as far below the o 
line of the erring eye was deviated above. 

The same figure, inverted, gives the explanatieS^of the diplopia in the 
case of deviation downward ( strabismus deorsfihfcvergens) of one eye, in 
which there is produced, necessarily, the ^mp^false projection as in the 
upward strabismus, only in the inverse sfois^r 

Finally, let us suppose that the e}^£)mstead of having been deviated 
by rotation around the vertical axie^^ the transverse axis, has undergone 
a pathological rotation around t^^antero-posterior axis , so that, for in¬ 
stance, the vertical meridian ^K^jS&e retina is inclined outward, towards the 
temple. ^ 

If this happen to t S^Jeft eye, as shown in Figs. 5a and 56, which 
illustrate the conditktfijof the two eyes as recognized from behind, the 
visual disturbance .<2r :ch results from it can be easily determined. The 
image yx of a^sffifcal line will coincide in the normal, the right eye (It) 
with the ve^lrad* meridian ( VV) of the retina. In the left eye, whose 
meridian > which ought to be vertical, leans outward, the image yx 
will angle with that meridian. Hence the object will seem to 

be infnWd, in its turn. 



In order to determine the direction of the inclination, we suppose the 
eye to have resumed its normal position. (Fig. 5c.) Then the meridian 
VV of its retina, which is normally vertical, becomes vertical, and the 

Fig. 5 a. 

Fig. 56. 




/ y 

\ X 

Fig. 5 d. 

upper extremity of the (; y ), which corresponds to the lower extremity 

of the object, is sit/iat|fcr to the inner (nasal) side. Hence the image of 
this point will be^eeiTTo the outer side, towards the temple. ( Y y Fig. 5 d.) 
The lower end„^M^ of the image, which falls on the temporal part of the 
retina, will be^**ojected inward—that is to say, towards the nose (X, Fig. 5d) 
—and ;ct will seem to be inclined, as is shown by the line A' l'. 1 


false image is not to be confused with the projection of the accidental image. 
beWcidental image is only the vertical meridian of the eye marked by a line whilst the 
ridian was in its correct position (only the affected eye fixing). When the eye turns and 



It will, without explanation, be seen that here, again, the degree of ap¬ 
parent inclination of the image is equal to that of the pathological rotation 
of the eye. 

Hence it must be understood that the false image is always the inverse 
of the direction and the position of the paralytic eye. With a nasal (in¬ 
ternal) deviation, the false image is temporal (external); or again: con¬ 
vergent strabismus is accompanied by homonymous diplopia.—With a 
temporal (external) deviation, the false image is nasal (internal); therefore 
divergent strabismus is characterized by crossed diplopia.—In upward de¬ 
viation (strabismus sursum vergens), the false image is inferior.—In down¬ 
ward deviation (strabismus deorsum vergens), the false image is superior. 
—Pathological temporal inclination of the eye produces nasal obliquity of 
the image, and a median (nasal) inclination of the eye temporal obliquity 
of the image. 

Since the false image is always situated in a position and direction 
contrary to those of the diseased eye, and the deviation is the contrary to 
the direction which the eye takes when it is normally acted upon by the 
muscle, the false image must correspond, in all respects, with the direction 
which the muscle normally gives to the visual line as well as to the 
meridians of the eye. 

The red line which on the following pages stands for the false image 
corresponds, therefore, at the same time, to the direction and the inclina¬ 
tion that the muscle in question imparts normally to the eye. It is only 
necessary to substitute the vertical meridian of the eye for the false image, 
and the pathological scheme will have been transformed into a physio¬ 
logical one, exhibiting the normal action of the ocular musclogV 

The diplopia which results from the paralysis of an ociH^nAiscle neces¬ 
sarily gives great annoyance to the patient. He is teadibled in making 
his way about. If he sees two objects instead oLm, he is not certain 
which is the true one. If the double images M^-qiartly superimposed, 
whether because the paralysis is not complet<yT»^ecause the object is too 
large or too near, the latter appears deformed. To obviate these and 
other inconveniences with which we steflN later become acquainted, the 
patient closes one eye, thereby sacrificing binocular vision. Sometimes he 
has recourse to another plan : he (fifetitutes a rotation of the head for 
the defective rotation of the ey^S 

If, because of paralysis of{raeleft external rectus muscle (Fig. 6a), the 
patient cannot turn the coi\gs)bonding eye towards the temple, he will turn 
his head in the same <>si^ation, until the visual line of his left eye (LX) 

- —— -- 

the meridian inclin^^nW image turns with the eye and is projected with the same lateral 
inclination that tl^^^mian has assumed. 

The false imag\corresponds to the projection of an image which the eye receives while 
it is in an incQfrc&ct position. Hence it is projected in the opposite direction from the in- 
clination^o^^^ meridian of the eye (Fig. 5d ),—that is, in the inverse direction of the 
patholograd rotation of the eye. 



is directed towards the object ( 0 ) that is fixed by the right eye. (Fig. 6b.) 
He thus sees the object binocularly, and the diplopia will disappear. In 

Fig. 6a. 




If, on the contrary, there is a deficient amount of motility upward (strabis- 
mus deorsum vergens ), he will direct his head upward. 

If his eye has undergone a pathological rotation around its antero- 

Fig. 6b. 



Finally, if one of the patient’s eyes has undergone a pathological rota¬ 
tion at once upward, inward, and around the visual line to the left, he will 
direct his head downward and outward, and will incline it towards the 
right side. 

Hence it will be seen that the corrective direction of the head is opposite 
to the direction and position of the paralyzed eye, and is identical with the 
projection of the false image. The patient turns his face towards the false 
image and inclines his head as the latter is inclined. Indeed, the false image 
corresponds to the direction and to the inclination which the paralyzed 
muscle, when normal, exerts upon the eye; and it is to make good the 
lost action of the muscle that the patient turns his head. 

The colored lines on the following pages may claim, therefore, a third 
meaning. They not only show the direction and position assumed by 
the eye under the influence of the normal contraction of the muscle, as 
well as those of the false image in the case of paralysis of the muscle, but 
they indicate also the direction and corresponding corrective position of the 

It has been seen that the patient can put an end to the diplopia, bring 
about the fusion of the double images, and direct both his eyes simul¬ 
taneously upon the fixation-object, by turning his head in the direction 
opposite to his strabismus. He ought to be able to secure the same re¬ 
sult by keeping his head still and displacing the object in the direction in 
which his eye is deviated. Let us consider Fig. 6b. It is necessary only 
to turn the diagram till the median line MA is directed forward. Then the 
object 0 will be at the right, and will be as readily fixed by the normal 
right eye as by the left eye, whose external recti^^\)aralyzed. This is 
what really happens. The diplopia diminishes ipS*roportion as the fixa¬ 
tion-object moves in the direction of the d<^Mon of the eye. On the 
contrary, the distance between the two im©p increases, when the object 
moves towards the side of the paralyzed ^Steele. The two images separate 
more and more from each other; tl^eMfe image seems to move from the 
object in the direction of the paralj^ecfmuscle. In the first case, the object 
enters more and more into the d^ain of the muscles that are acting nor¬ 
mally and are capable of ass^^ing their action with that of the muscles 
of the sound eye. On the ^j^^jary, in the second case, the object enters into 
the sphere of action of^™^aralyzed muscle, whose defect makes itself felt 
increasingly in pr qpo^n as the object is carried farther in that direction. 

Hence the angi^^f strabismus—that is to say, the separation of the 
visual lines oflElje two eyes—has nothing absolute about it; it may be¬ 
come nil in direction of the deviation, while it increases in the direc¬ 
tion of 4faC>hralyzed muscle. 

In>^$ler to avoid confusion, the term angle of strabismus, properly so 
callA is used to designate the angle that is formed by the lines of sight 
the healthy eye is directed straight forward towards an infinitely dis- 
“tant obiect. 



The domain within which the lines of sight of the two eyes may meet in 
the same point of fixation—in other words, the domain of the fusion of the 
two images —is more limited in proportion as the paralysis is more nearly 
complete. This domain of binocular single vision is separated from the 
domain of the double vision by a fairly distinct line of demarcation for 
the paralysis of different ocular muscles. 

Fig. 7. 

The curve in Fig. 7 represents the diplopia of a patient afflicted with paresis of the left external 
rectus, having produced a convergent strabismus of 14 degrees. 

The numerals along the horizontal line indicate, in degrees, the excursions of the eyes from the 
zero-point, which corresponds to the primary position,—that is to say, looking straight ahead. The 
numerals on the vertical line indicate the degrees of the strabismus and of the diplopia. 

It will be seen that, when the patient directs his eyes towards the right, at an angle of 37°, the 
diplopia disappears in consequence of the fusion of the double images. On the contrary, when he 
looks towards the left, the diplopia increases. It amounts to 14° when he looks straight ahead, and 
to 25° when he looks forty degrees in the direction of the paretic muscle. 

Fig. 8. 



'£ 0 ° 


15 ® 


> ] 

10 ® 








The curve in Fig. 8 represents the diplopia of. 
In this case, the diplopia extends over the 
the two images are still separated by tw< 
the nose hides the object from that eye. 
and it is then the image belonging ttyfrfed^ 
position, the diplopia, and, consequeiulyA 

' R 

nt having paresis of the right external rectus. 
Id of excursion. At an angle of 40° to the left, 
then that of the right eye disappears, because 
same angle to the right, the diplopia amounts to 35°, 
_ eye that disappears behind the nose. In the primary 
}he strabismus, amount to 15°. 

The domain of fij^iyn, the field of binocular fixation of the paralytic 
eye, is, moreover^nQfc wise equal to the common part of the superimposed 
fields of fixationS^SOrie two eyes. It is much more restricted than is the 
latter. \ ^ 

Thus, represents the horizontal extent of the excursions of the 

l e ft eye ^^one of my patients having paresis of the external rectus , with a 



convergent strabismus of 8°. This field of fixation is limited on the outer 
side, where it reaches only 22°, while its nasal limit shows no alteration, 
measuring as much as 48°. 

The excursions of the right eye are normal. They go to 48° on both 
sides. (Fig. 9 b.) 

In Fig. 9c the two fields are superimposed. It is evident that the zone 
which is common to them is quite extensive. It goes from 22° at the left 

Fig. 9a. 

Fig. 96. 





22* 0* 

48 * 

48 * 0 * 

48 * 

Fig. 9c. 

to 48° on the right. But examination of the binocular vision demon¬ 
strates that the fusion of the two images commences only at an angle of 
38° to the sound side. Hence the field of binocular fixation in the hori¬ 
zontal meridian has an extent of scarcely 15°, instead of the 70° which 
are common to the excursions of the two eyes in this meridian. In other 
words, if the two eyes command this space with the excursions of their 
lines of sight, they do not command it simultaneously . 

Still, this fact has nothing surprising about it. in a case of paresis, 
the sick eye can still move to a certain degree in posite direction from 

its deviation, this movement requires of the eaMMed muscle, necessarily, a 
much greater effort than if it were normaJjCpacl more than it does of the 
associated muscles of the other, the he&^jjiy eye. Hence we need not be 
astonished if the two eyes succeed>fw^Owith difficulty in associating their 
movements, even in the space wWcBwdch, by itself, commands. 

The abnormal effort whiclv4Se enfeebled muscle is obliged to make 
theS ives rise to sti11 otller vei T important 

£k a of Fig. 2, which represents a case of paral- 
lis of the left eye, and suppose that the other eye 
being blind or covered by a diaphragm. The 
patient wislies^o^x the object 0,—that is to say, to give his eye, L , such a 
direction thaKtfie image of 0 may be formed on its fovea centralis, /. If 
the paj'q^$< of the abducens be complete, there is nothing left for the 
pati^ftJN^ do but to turn his head towards the left, through an angle equal 
to tiuNfeviation of the eye, or to carry the object to the right, until it is on 
OiJ^psiial line /£. 

V But suppose there is only paresis , and that the external rectus has re- 

when it tries to move 

Let us resume co 
ysis of the external 
is excluded fr 



tained enough contractility to direct the eye towards the object. This rota¬ 
tion, executed by a paretic muscle, necessitates a stronger nervous impulse 
in proportion as the muscle is weaker. 

Now, it is by the aid of the muscular sense that we make our way about, 
and particularly by the aid of the sense of the oculci7' muscles . 

The patient affected with paresis of the left external rectus will, then, 
suppose the object fixed to be so much the more to the left side, as he has 
brought more energy into play in order to reach it with the visual line. 

If, guided only by the paretic left eye, he hastens towards an open 
door, he runs the risk of a collision with the left side of the door-frame. 
Hence the very characteristic gait of such a patient: instead of going 
straight towards the point of destination, he at first goes too much to the 
left, and it is only later, on perceiving his error, that he rectifies his course, 
often betaking himself suddenly to the opposite side, where the object 
actually is. For the same reason, he pours water to the left side of the 
glass; instead of dipping his pen in the inkstand, he puts it to the left 
side of the stand, etc. 

This false projection, as it is called, necessarily takes place always 
in the direction of the normal action of the paretic muscle, exactly like the 
projection of the false retinal image which gives rise to diplopia. 

However, the two phenomena must not be confounded with each other. 
They are not at all identical. Diplopia is produced even when the eyes 
are at rest in their position of equilibrium, and results, as we have ex¬ 
plained, from the comparison of the place in the retina where the image is 
formed in the healthy eye, with the one where it is produced in the deviated 

eye * A 

False muscular projection does not come into play until the moment 
when an effort is demanded of the paretic muscle. Halstead of direct¬ 
ing the deviated eye towards the fixation-object, the ^pbtient displaces the 
latter or turns his head so that its image is redASd on the fovea cen¬ 
tralis without any effort of the affected muscle^© will not be deceived as 
to the position of the object. Thus, the fals^ projcction diminishes in the 
direction of the deviation , while it increases in the direction of the 'paretic 
muscle. ^ 

Hence this pathological phenomenon to which the paralysis gives rise 
follows also from the physiolqgi^ Action of the muscle. To a person 
one of whose abductors is parartvied, the ambient world will seem displaced 
towards the affected side.—-^fJrF be the internal rectus that is paretic, the 
false projection will l*e ^awards the healthy side.—In the same way, the 
hand will seek an objeeiNSelow its real position, and at the temporal side 
of where it real! Len the patient fixes only with an eye affected with 

paresis of the sm^por oblique. 

The falseJUjrhjection becomes especially manifest, when one asks the 
patient toN^sapidly with his finger an object located on the side of the 
paralyzed muscle. 




In order that this experiment may succeed, it is indispensable to hide 
from the patient the hand with which he is to touch the fixation-object. 
Otherwise, the image of the hand being formed on the same retina with 
that of the object, he will rectify the false muscular projection by the 
correct retinal projection. The simplest means of succeeding in this, is to 
place a large piece of cardboard between the patient’s neck and the wall 
on which the fixation-point has been marked. The patient is then to direct 
his index finger, under the cardboard, towards the place where he supposes 
the point, fixed by his paretic eye, to be. 

Donders advises that the patient’s eye be closed while he points out the 
location of the fixed object. It is easy to convince one’s self that, under 
these circumstances, a healthy person will always point correctly, while 
the ill one will point wrong and too far in the direction of the paralyzed 

Let us see, now, what the sound eye is doing while the ill one is fixing. 
This is easy; for, in order to exclude the sound eye, we need not cover it 
entirely, provided we hide the fixation-object from it. We thus learn that 
the healthy eye is deviated in the direction in which the paretic muscle turns 
the affected eye. 

For instance, in a case of paresis of the external rectus of the left eye , the 
right eye squints towards the left when the left eye fixes alone. If the left 
(fixing) eye be the victim of paresis of the superior rectus , the right eye is 
directed upward and to the right ,—that is to say, towards the side to which 
the paretic muscle would have directed the left eye. 

Finally, if the paretic muscle turns the eye around its antero-posterior 
axis, inclining the vertical meridian , for instance, towards the nose, as does 
the superior rectus, the sound eye will execute an analogous rotation (towards 
the temple in this example) when the affected eye *&^e is fixing. 

The deviation which the healthy eye underg*^ while the paretic eye is 
fixing, is called secondary deviation. Lfc^may be considered as the effect 
of the paretic muscle acting upon the healthy^eye. 

In order to represent the direc^i3k\|ind inclination assumed by the 
healthy eye while the ill eye is one need only consider the red 

lines of our special part (pages 2@^8), but interchanging the letters. For 
instance, in case of paresis of(0»e left eye, the letter R will be substituted 
for L , and the red line wiliwpresent the secondary deviation of the right 
eye while the affected left eye fixes. This is, therefore, a fourth signification 
which the accompanyiCg> diagrams may claim. 1 

The secondary (Wiation is especially striking when, the fixation-object 
and the patienjforQ?ad being immobile, each eye is successively covered and 
uncovered. />KWe deviation then manifests itself not only directly to the 

Jie diplopia resulting from the secondary deviation is directly deducible from the 
pdHjjff&n of the sound eye. The image corresponding to it is, in all points, the inverse of 
^is position. 



view, but also by the correcting movement that the eye is forced to make in 
order to direct itself towards the fixation-object. 

On making this experiment carefully, one sees a phenomenon which 
is one of the most important for the diagnosis of paralysis of the ocular 
muscles. It is that the secondary deviation (of the healthy eye) is always 
more extensive than the primary deviation (of the paretic eye). 

An intelligent patient readily perceives that, when he fixes with the 
affected eye, the diplopia and apparent inclination are considerably stronger 
than when he fixes with the healthy eye. 

This phenomenon is explicable as follows. The movements of the 
eyes are associated; one of them cannot be moved unless the other is. If 

one of them goes from right to left, for instance, the other follows, it, so 
that the internal rectus muscle of the right eye may be considered the 
associate of the external rectus of the left eye. Under normal conditions, 
therefore, the two always receive the same nervous impulse. 

Now, if, in consequence of paresis, the left external rectus claims a 
stronger nervous impulse than usual, in order to direct itself towards the 
object fixed, the intact internal rectus of the other eye will respond to 
this surplus of stimulation by a surplus of rotation, which it will com¬ 
municate to the eye to which it is attached. The right eye will be turned 
inward more than the left one is, when the right eye fixes. Indeed, the 
left eye squints only because it abandons itself to the preponderance which 
the internal rectus assumes over the enfeebled externus, but not in conse¬ 
quence of an active contraction of the former. 

The same is true in the case of the superior rectus. If that of the left 
eye be paralyzed, and we oblige the patient to use that eye alone for vision, 
he will bring into play more than normal innervation, in^ntfcrc^ to direct 
the eye in the sense of the paretic muscle—that is to upward and 
towards the nose—and to counterbalance the effect of i^Qtotagonists. The 
same effort will turn the healthy eye upward andy^Tgntly outward, more 
than it does the affected eye : so that the diffei^Q^yf height as well as the 
divergence will be much more marked durinJ^J^^fixation of the affected 
,eye than during that of the healthy eye. same thing occurs in the 

case of rotation around the antero-postermf axis. The effort which the 
affected eye makes to restore its vedwl meridian leaning towards the 
temple, will impose upon the sourf^at^ a much more marked inclination 
towards the temple on its side. /*vV 

The case is not rare wheifeuymie is uncertain not only as to which of the 
eyes is the affected one, whgre tnere is paresis of an abductor or an adductor, 
but also as to which levators or depressors is paretic, and to which 

eye it belongs. If even happens that, the visual value of the two eyes 
being very difforara^it is the better of the two which is the victim of 
muscular paresie. In such a case, the patient continues to “use that eye for 
fixation, an^Tye^ other deviates. One is then the more tempted to consider 
the lattei^^ fne paralytic eye as its deviation is more marked. More than 


once patients have come who have, for months, had electricity applied to 
the healthy eye instead of to the affected one. 

The examination of the field of fixation and the study of diplopia, but 
especially that of the secondary deviation, will guard us against such an 

Moreover, we shall become acquainted with a form of strabismus wherein 
the deviation is sensibly the same for both eyes. The secondary deviation 
will help us to distinguish the two kinds of strabismus one from the other. 
Hence it constitutes, from more than one point of view, a most precious 
means of diagnosis. 

"We have demonstrated 1 that the difference between the secondary and 
primary deviations is equal to the angular value of the false projection . 

If, for instance, the patient has convergent strabismus amounting to 8°, 
in consequence of paresis of the left external rectus, and if, when fixing 
with the affected eye, there is present a secondary deviation of 12°, he 
will suppose the fixation-object to be 12° — 8° =4° to the left of its real 

There is nothing surprising about this fact: both phenomena are due 
to the same cause. Each is the expression of the surplus of innervation 
required by the paretic muscle. This excess of nervous impulse provokes 
an excess of deviation of the sound eye, whilst it manifests itself, on the 
affected eye, as an error of orientation, as false projection. 

r£sum£ of the general symptomatology of paralysis of the 


We have become acquainted with a series of phenomena to which paresis 
of an ocular muscle gives rise, and we have seen th^Hjie^ may all be reduced 
to the action of that muscle upon the eyebj normal circumstances. 
These phenomena are produced either in th£>6ame direction in which the 
muscle turns the eye, or in the opposite tion. 

Let us arrange these phenomena columns, and we shall have our 

symptomatology reduced to its sirapksr expression. 

There are produced— 



In the sense of the physioloyice^&fion of 
the muscle: 

(Red lines of special part 
1. The defect of the j(P t'W&on, —limitation 
of the field of 

3. Th q false zmr^r^«increase of diplopia. 

5. The directiowwjlic face. 

6. ThefalfeJb&jJction. 

7. The s^S^kry deviation of the sound eye. 



In the opposite sense from the physiological 
action of the muscle : 

2. The deviation of the eye ,—the strabis¬ 

4. The diminution of the diplopia ,—the 

1 Landolt, Archives d’ophthalinologie, Mai, 1893. 




When we bear in mind the anatomy and physiology of an ocular muscle, 
nothing is easier than to find, by the help of the rules that we have just 
laid down, the phenomena to which its paresis must'give rise. We shall, 
therefore, for each of the muscles preface the symptomatology by a brief 
anatomical 1 and physiological resumL 


The external rectus takes its origin at the optic foramen, is directed 
forward and outward, and is inserted 7 millimetres from the temporal 
margin of the cornea. (Fig. 10 and Fig. 17, EE.) The muscular plane is 

Fig. 10. 

M, centre of motion; AA, antero-posterimAgm; RR, axis of rotation of superior and inferior 
recti, forming an angle of 63° with AA ; Quotation of superior and inferior oblique muscles, 

forming an angle of 39° with A A (the r^m^tes, perpendicular to the axis of rotation, indicate the 
corresponding muscular planes ); P, mtUey (Jruchlea) of superior oblique muscle. The rectus superior 
of the right eye has been removed, rrhej insertion of the inferior oblique is rarely visible from above; 
it can be seen better from the tempontande (Fig. 17). Oh, chiasma.— E. Landolt del. 

horizontal, the axis o^Tytation vertical; hence the external rectus turns the 
cornea strictly tqw^Pte the temple, without producing any inclination of the 
vertical meridmhv 

Paresis tne External Rectus.—The excursion of the eye is limited 
towards pie,—that is to say, towards the side of the affected eye. 



1 Fuchs, Archiv fur Ophthalmologie, xxx., 4, S. 1 et seq. 



The eye is deviated towards the healthy side, —convergent strabismus. 
The false image is on the same side with the affected eye ( homonymous 
diplopia ), is parallel to that of the other eye, and on the same level with it. 

The diplopia increases towards the side of the affected eye, and dimin¬ 
ishes at the side of the healthy eye. 

The false projection takes place towards the affected side. 

The face is directed towards the side of the affected eye. 

The secondary deviation of the healthy eye is towards the affected side 

Fig. 11a. 

Fig. 116. 



Relative position of the double images in paraly¬ 
sis of the external rectus of the left eye. 

Relative position of the double images in paraly¬ 
sis of the external rectus of the right eye. 

Fig. 12. 

(convergent strabismus), and the diplopia is still homonymous, only more 
pronounced than when the healthy eye fixes. 

We give in Fig. 12 the field of fix¬ 
ation of a case wherein paresis of the 
external rectus has brought about con¬ 
vergent strabismus of 8 0 . 1 

When an eye affected by paresis of 
its external rectus reaches the temporal 
limit of its field ofi excursion, one often 
sees it oscillatoii^w^ird and downward 
by virtue ofcrfhe contraction of the 
obliqui whjQSare trying to supply the 
insuffi^n^hbducent action of the para- 

Field of fixation of a left eye affected with O INTERNAL RECTUS 

paresis of the external rectus. (The dotted line/"^S 
corresponds to the normal field of fixation.) %J The internal rectus originates at the 

optic foramen, and is directed forward 
and towards the median pl^M> be inserted 5.5 millimetres from the inner 
corneal margin. (Fig. f^OsrThe muscular plane is horizontal, and its axis 
of rotation vertical./-HeAce the internal rectus turns the cornea directly 
towards the nose witfWt inclination of the vertical meridian. The external 
and internal rect^Jb antagonists. 

Paresis of the Internal Rectus.—The excursion of the affected eye 
is limited^^bhe side of the healthy eye. 

The is deviated towards the temple,— divergent strabismus. 

SO, i. d 



also an analogous fixation-field, Landolt, Archives d’Ophthalmologie, 



The false image appears on the side of the healthy eye; it is parallel 
with that of the other eye and on the same level,—simple crossed diplopia . 
The diplopia increases towards the side of the sound eye, and diminishes on 
the side of the affected eye. 

The face is directed to the side of the sound eye. 1 
The false projection is towards the healthy side. 

The secondary deviation is towards the healthy side (divergent strabis- 
Fig. 13a. Fig. 136. 


Relative position of the double images in paraly¬ 
sis of the internal rectus of the left eye. 

Relative position of the double images in paraly¬ 
sis of the internal rectus of the right eye. 

Fig. 14. 

mus); hence the diplopia is still crossed, only more pronounced when the 
sound eye fixes. 


The superior rectus originates at the optic foramen. (Fig. 10.) It is 
directed forward, upward, and slightly outward, to be inserted 7.7 milli¬ 
metres from the upper corneal margin. 

—The muscular plane is vertical, but 
forms an angle of 27°, opening out¬ 
ward, with the median plane. (A A, 

Fig. 10.) Its axis of rotation (RR, 

Fig. 10) is sensibly in the horizontal 
plane, and forms with the antero-pos- 
terior axis an angle of 63°, its median 
extremity directed forward.—The su¬ 
perior rectus directs the eye upward 
and inward, and inclines the vertical 
meridian towards the nose. 

Paresis of the Superior Rectus 
—Excursion defect upward and t 
wards the healthy side. (Fig. 1 ^Zr > 

Deviation of the eye dow^roar 
and towards the affected s * 

Fixation-field of a left eye affected with paresis 
of the rectus superior. 

Strabismus deorsum vergens , and slightly 


1 It is to be noticed Jij© a patient whose face is turned towards the left may be af¬ 
fected with paralysis AS^her the left external or the right internal rectus. Indeed, these 
two muscles turn fl|^yes to the left. Hence their paralysis necessitates the same com¬ 
pensatory rotationjof rhe head. But the differential diagnosis in such a case presents no 
c ifficulty, sin^yl^ilysis of the externus produces convergent and that of the internus 
divergent strabismus. 



The vertical meridian is inclined towards the temple. 

Vertical and Slightly Grossed Diplopia .—The image of the diseased eye 

is higher than that belonging to its fellow-eye, and slightly inclined towards 
the nose. (Figs. 15a and 156.) 

Fig. 15a. 

Fig. 156. 

Relative position of the double 
images in paralysis of the rectus supe¬ 
rior of the left eye. 

Relative position of the double 
images in paralysis of the rectus supe¬ 
rior of the right eye. 

The difference in height between the two images increases when the patient 
looks upward , and also when he looks towards the diseased side . In this 
case, the line of sight takes the same direction as the rectus superior muscle 
(or, what amounts to the same thing, is directed perpendicularly to the axis 
of rotation of this muscle). The latter then becomes a pure levator, and 
the defect in elevation of the eye, resulting from its paralysis, makes itself 
so much the more felt. vOi 

The inclination of the vertical meridian ancfjimt of the false image 
diminish at the same time. 

The inverse takes place when the pal^e^^looks towards the healthy 
side. In this case, the line of sight of th^mfeeased eye approaches the axis 
of rotation of the muscle, and the lattdk instead of raising the cornea, rather 
turns it around the line of sight. ^jHence, when the muscle is paralyzed, 
the action of its antagonists make^iiself felt not so much in depressing the 
eye as by a pathological rotati^hround the visual line. 

Consequently the diffwtptt{tfi height of the two images diminishes when 
the patient looks towam^me side of the healthy eye , while the inclination 
of the false image i/tcrZmes at the same time. 

The vertical dmtupia diminishes still more when the patient looks 

The irected upivard , and there is a tendency to incline the head 

toward^fr^wiouMer of the healthy side , in order to obviate the inclination 
of the^faltee image. 

\s£Tl^false projection is upward and towards the healthy side. 

X The secondary deviation of the healthy eye is upward and towards the 


healthy side, with temporal inclination of the vertical meridian. Hence 
there is, in this case, a difference in the height of the two images; that 
belonging to the. healthy eye being the lower, on the opposite side (crossed 
diplopia), and inclined towards the side of the diseased eye. 


The inferior rectus takes its origin at the optic foramen. (Fig. 10.) 
It is directed forward, downward, and slightly outward, to be inserted 6.5 
millimetres from the border of the cornea, obliquely, its nasal extremity 
being more advanced than its temporal. The muscular plane, as well as 
the axis of rotation ( RR , Fig. 10), is sensibly the same as for the superior 

The inferior rectus turns the cornea downward and inward , and inclines 
the vertical meridian toivards the temple. 

Paresis of the Inferior Rectus.—Defective motility downward and 
towards the healthy side. 

Eye deviated upward and towards the diseased side. Strabismus sur - 
sum vergens , and slightly divergent. The vertical meridian is inclined to¬ 
wards the nose. 

The false image is the lower , is on the side of the sound eye (vertical 
and slightly crossed diplopia), and its upper end tends towards the temple. 
(Figs. 16a and 166.) 

Fig. 16a. Fig. 166. 

Relative position of the double 
images in paralysis of the inferior 
rectus of the left eye. 

Relative position of the double 
images in paralysis of the inferior 

rectus of the right eye. 

The difference in heighifTpween the two images increases when the 
patient looks downward , especially when the affected eye is directed towards 
the diseased side, becau&^pTen the inferior rectus becomes a pure depressor 
and loses its actioq ^^rrotator around the line of sight. This is why the 
inclination of th^^Stf&Cidian and, consequently, that of the false image de¬ 
crease in this caseS 

On the^onfyary, the inclination of the image increases and the vertical 
diplopia diminishes when the eye is carried toivards the healthy side, because, 


on directing itself perpendicularly to the muscle implicated, the eye under¬ 

goes only rotation around its visual line, which then coincides with the axis 
of rotation of the muscle. 

The vertical diplopia diminishes when the patient looks upward and 
towards the healthy side.—The inclination of the image diminishes when the 

patient looks towards the affected side . 

The face is directed downward and towards the healthy side , and slightly 
inclined over the shoulder of the diseased side . 

Secondary deviation of the sound eye : downward and to the healthy side; 
its vertical meridian leans towards the nose: hence the image which cor¬ 
responds, under such conditions, to the healthy eye is the higher, on the 
opposite side (crossed diplopia), and is inclined towards the temple. 


The inferior oblique takes its origin from the anterior and inner part 
of the floor of the orbit, at the margin of the naso-lacrymal canal, and is 

directed backward and outward, around the eyeball, 
to be inserted on its posterior, external portion, just 
under the horizontal meridian. We have indicated 
this insertion, in Fig. 10, by a little red mark ; in 
reality it is not quite visible from above. It presents 
itself wholly on the temporal side. (Fig. 17.) 

Fig. 17. 

"tg 7 The muscular plane is vertical and forms an angle 

- of about 51° with the median plane. The axis of 

Right eye seen from rotation (00, Fig. 10) is sensibly in the horizontal 

Of motion; EE, insertion P lane > forming with the antero-posterior axis an angle 

of rectus externus; 01, ono -*— — x - J 

insertion of obliquus in¬ 


Paresis of the Inferior Oblique.—The^gjpursions of the eye are limited 
upward and to the affected side. 

The eye is deflected downward and xgjcwds the healthy side . Strabismus 
deorsum vergens , and slightly convexfait. 

The vertical meridian is incUned^towards the nose . 

The false image is the hitfkenf and at the side of the diseased eye. Ver¬ 
tical and slightly homonyi^^^T&plopia. The upper end of the image leans 

»n the contrary, the inclination of the meridian and, consequently, that 



of the false image are more accentuated when the gaze is towards the ill side; 
for, if the line of sight coincides with the axis of rotation of the oblique 
muscle, the latter turns the eye only around this line of sight, instead of 
elevating or lowering it. 

Fig. 18a. 

Fig. 186. 


Position of the double images in paralysis of 
the inferior oblique of the left eye. 

Position of the double images in paralysis of 
the inferior oblique of the right eye. 

Diplopia diminishes when the gaze is downward and towards the well 

The face is directed upward and towards the diseased side , and the head 
inclines over the shoulder of the affected side. 

The false projection is upward and towards the affected side. 

The secondary deviation of the sound eye is upward and towards the 
diseased side (strabismus sursum vergens , and convergent ), with inclination 
of the vertical meridian towards the ill side. 4 

Hence the corresponding diplopia is vertical and homo^^mo^is. 

The image of the eye which does not fix (the health^ Iw) is the lower, 
and inclined towards the temple. 


In order thoroughly to understand th<> phenomena to which paralysis 
of the superior oblique gives rise, the pulbr^Sn the fossa trochlearis—that 
is to say, on the nasal side of the edge^fthe orbit, in front of and above 
the eye—must be regarded as its origtiS, From there, the muscle is directed 
obliquely backward and outwardSqj^L fs inserted at the outer posterior and 
upper part of the eyeball, ajap^ftv^is far to the rear of the equator as the 
insertion of the rectus superiorjis in front of it. (Fig. 10.) 

Its muscular plane an<Jwts axis of rotation (00) are virtually the same 
as those of the inferioi^abnque. The superior oblique directs the cornea 
downward and and exerts upon the vertical meridian an inclina¬ 

tion towards the 

Paresis of the Superior Oblique.—The excursion is restricted below 
and towa^^ehffected side. (Fig. 19.) 

The ey^ is deviated upward and towards the healthy side (strabismus 


* 9 ' 



Fig. 19. 

sursum vergens, and slightly convergent ), and the vertical meridian is inclined 
towards the temple. 

The false image is below the real one and to the side of the ill eye (ver¬ 
tical and homonymous diplopia). It is, 
moreover, inclined towards the healthy 
side, (Fig. 20.) 

The difference in height increases 
when the patient looks downward , espe¬ 
cially when the eye is directed towards 
the healthy side. 

The obliquity increases when the 
gaze is towards the diseased side , for 
the reasons given when we were dis¬ 
cussing paralysis of the inferior ob¬ 

Hence the difference in height and 
the obliquity increase and decrease in 
inverse proportion. 

Vertical diplopia increases in pro¬ 
portion as the patient looks downward as well as towards the healthy side. 
Obliquity increases when the patient looks towards the diseased side. 

Fixation-field of a right eye affected with 
paresis of the superior oblique. (Landolt, Arch. 
d’Opht., 1881, p. 606.) 

Fig. 20a. 

Fig. 20 b. 



Position of the double images in paralysis of the 
superior oblique of the right eye. 


Position of the double images in paralysis of^Ete 
superior oblique of the left eye. ^ 


The false projection^^pmiward and towards the diseased side. 

Secondary Deviatiti 7y^-When the diseased eye is fixing, the healthy eye 
deviates downwarciQiijno wards the affected side; its vertical meridian leans 
towards the tejnjjJ^. Hence the image belonging to it is above and on the 
same side (hqrafciymous diplopia) and inclined to the affected side. 

Paresis of the Third Pair, or Common Motor Oculi. —Among the 
muscle^s^ose paralytic phenomena we have just been studying, there are 
only^wo —the first (external rectus ) and the last (superior oblique )—that 
^Qfcnfervated by a special cranial nerve ; the former by the sixth pair (ab- 
<2^cens) and the latter by the fourth pair (patheticus). The other muscles 



—the internal , the superior and inferior recti, and the inferior oblique —are 
all animated by the third pair, the common motor oculi. That explains 
why isolated paralysis of the external rectus, as well as of the superior 
oblique, is not rare, while the other ocular muscles are almost always 
affected conjointly, at least to a certain degree. 

Therefore paresis of the common motor oculi will be characterized by a 
considerable limitation of the fixation-field. (Figs. 21 and 22.) Excur¬ 
sion towards the healthy side , upward , and downward will be noticeably 
restricted . 

Fig. 21. 


Fixation-field of a right eye having paresis of 
the common motor oculi. 

Eig. 22. 


Fixation-field of a right eye having paresis 
of the common motor oculi more advanced than 
that of Fig. 21. 

The eye, whose external rectus and superior oblique act almost without 
antagonists, deviates towards the diseased, side (divergent strabismus ), and 
often somewhat downward , by virtue of the action of the superior oblique. 
The latter symptom is not always manifest, however, bectW^af the ab¬ 
duction due to the external rectus, which interferes with th^CJ^wering action 
of the superior oblique. 

The nasal inclination of the vertical meridian, nft|peed by the superior 
oblique, is, on the contrary, rather marked, andvbrfQies especially so when 
the patient looks downward, because then alljtiWnergy brought into play 
bears on this single remaining depressor. 

The image belonging to the paralytic^e is on the opposite side ( crossed 
diplopia ), is generally somewhat higheQmcl inclined toivards the temple,— 
that is to say, towards the image b&£*|ing to the sound eye. 

The horizontal separations fQjio two images increases when gazing 
towards the healthy side . 

A difference in AeA/A^^Sjadded to this and increases as soon as the 
patient looks upward- ov^mward. In both cases, the false image seems 
to flee before the tm^ne, so that it is the higher when the patient looks 
upward, and the to^i'when he looks dowmcard. 

The the image increases especially when the patient looks to¬ 

wards the flfey side. The horizontal diplopia diminishes at the same time. 



The head is turned towards the healthy side and upward, especially 
when there is partial ptosis, and, moreover, is inclined over the shoulder 
of the diseased side. 

The false projection is towards the healthy side. 

Secondary deviation consists especially in a strong divergence of the 
healthy eye. 

Paralysis of the common motor oculi, moreover, most of the time pro¬ 
duces that of the levator of the upper lid, as well as of the intrinsic muscles 
of the eye, the sphincter pupillse and the ciliary muscle . 

The phenomena to which it gives rise—the ptosis, mydriasis, and pare¬ 
sis or paralysis of accommodation —are most characteristic, and constitute, 
when they are combined with that of the motor muscles, an aggregate of 
symptoms concerning which one could scarcely err in diagnosis. 

This is especially true when the paralysis of the third pair is complete. 
The upper lid is then entirely closed, and the frontal muscle, making stren¬ 
uous but vain efforts to supply the action of the paralyzed levator, suc¬ 
ceeds only in wrinkling the skin of 
the forehead, raising the eyebrow, and 
stretching the curtain lowered over the 
diseased eye. 

When this eye is uncovered, it is 
found to be totally divergent and 
almost immobile, with its pupil dilated 
to a certain degree. 

It is evident that, in such a case, 
the sound eye could not, by secondary 
contractions, ^nfyduce all the symp¬ 
toms of the paralyzed eye and thus 
deceive bserver. 

&©ve have called attention to the 
fimjQRat, very often, the third pair is 
paralyzed for both eyes simultaneous^ so that, in any case wherein there 
is complete paralysis of the comnaSi* motor oculi of one side, there is occa¬ 
sion to seek also lesions in the^omain of that of the other eye. 

What is also interesting^ note is that in almost all cases of this 

Field of fixation of a right eye affected with 
paresis of the oculo-motorius and the abducens. 

kind there exists a liti 
in which the extern 
the eye 

s a lirmi^fS 
vfttliM obste 

of excursion also outward, in the direction 
freed from all opposition, ought to be able 
obstacle. (Fig. 23.) This fact leads us to con- 

to turn 
sider the 

Combined Paralyses of the Ocular Muscles. —Although generally 
a single♦nrapr nerve, with the muscle or muscles which it innervates, is 
paral^SJSve sometimes see several muscles of the same eye or of both 
eyes simultaneously paralyzed. 

have already mentioned the limitation of the temporal excursions 
( ^vyhich almost always accompanies paralysis of the common motor oculi, and 



which leads to a presumption of the simultaneous paresis of the abductor. 

(Fig. 23.) 

We have also observed some cases of double paralysis of the sixth pair. 
(Figs. 24a and 246.) 

Fig. 24a. 

Fig. 24 b. 







Fixation-fields of both eyes of the same person affected by double paralysis of the third and of the 

sixth pair. 

It happens, in the same way, that the associated muscles , as the external 
rectus of one and the internal rectus of the other eye, or both levators or both 
depressors of the two eyes, or the two adductors which preside over con¬ 
vergence, or the two abductors which preside over divergence, are paralyzed 
at the same time. The name associated paralyses has been given to 
those of the same type. 

Finally, all the motor muscles of one eye—indeed, even those of both 
eyes—may be paralyzed. From this results a complete imntbffility of the 
eye, which is called total ophthalmoplegia. iv * 

If this concerns only one eye, nothing is stranger to see the other 
move fieely in all directions, while the alfected eye ra^yhis stationary, as if 
fixed in its orbit. Usually ptosis preserves themrffrefrt from the intolerable 
diplopia which would result from the loss of t ^ej ujaociation of his eyes. 

When the ophthalmoplegia is double J< $&e patient is forced to make 
movements of his head take the place of tQse of his eyes. He will often 
be obliged even to use his hands to rakgjne of the upper lids which cover 
his pupils. \<sfb 

When one considers the sni^Mess of the space whence arise the motor 
nerves of the eyes, the comp^iUof their cerebral paths, and the relatively 
narrow opening through ghW they enter the orbit, one is not astonished 
that the same morbid caMOnay affect several of them simultaneously. 

The resulting sym^Mns are easy to deduce from what is above shown. 
The attentive otak&h- will even recognize, without trouble, in each case, 
the implicated muscles. 

If parey^W the external rectus is conjoint with that of the common 
motor fixation-field will inform us of this fact, as in the cases 



represented by Fig. 23 and Fig. 24. The crossed diplopia, characterizing 
paralysis of the third pair, may even, when the patient looks towards the 
affected side, be changed into homonymous diplopia, if the paralysis of the 
abducens is complete. 

Paralysis of the common motor oculi in both eyes , as well as paresis of 
both external recti , is easy to recognize. The latter gives rise to convergent 
strabismus with homonymous diplopia , which increases towards either side . 

The same is true of paresis of both internal recti: divergence , as well as 
crossed diplopia , increases towards the right as well as towards the left Such 
a case is, however, a comparatively rare one. The weakness with which 
both internal recti seem struck at times, often concerns only their associa¬ 
tion in the movement of convergence. This will be discussed in the second 
part of the article. 

The fixation-field will teach us, in such a case, concerning the power of 
the muscles in question. The nasal excursion of the eye is normal when 
it is a question of a functional disturbance of convergence, while it is limited 
in muscular paresis. 

The examination of the excursions of the eyes will determine our diag¬ 
nosis in all cases where diplopia is lacking. 


The influence of the different muscles upon the eyeball may be studied 
and demonstrated by means of an instrument we have had made, the 
ophthalmotrope . (Fig. 25.) 

A schematic eye, consisting essentially of three bands of metal for its 
vertical and horizontal meridians and its equator, withy a cornea attached, is 
so arranged as to be suspended in two stationary ^ings|one horizontal and 
the other vertical, by the three rotatory axes of ^^hiuscles. 

In order to show the action of the lateraf^bdi, we fasten the ends of 
the vertical axis by means of the two corr^^pading screws ( r ). 

The axes of the superior and 
muscles (00) can be seized betweej 
zontal ring. By fastening the sci^ 
In this way, even the most c£ 

w recti (JRR) and of the oblique 
screws connected with the hori- 
i, the eye is held in the position desired, 
ix action of the ocular muscles may be 

studied with ease. Take, 
superior and inferior 
upon three axes 
(abduction and a< 

instance, that of the obliques or of the 
hese muscles turn the cornea, so to speak, 
'rizontal (elevation and depression), the vertical 
ion), and the antero-posterior (inclination of the 

Owing tq-thu stationary rings of our instrument, which represent the 
immovabl^Q^nzontal and vertical meridians, it is easy to see not only the 
positioi^whch these muscles give to the eye, but also the extent of each 
of th% three rotations corresponding to a given degree of muscular con- 

thte tl 

t is, further, interesting to compare the action of the vertical recti with 



that of the oblique muscles. We may notice, for example, that, with the 
same degree of rotation, the inferior rectus lowers the cornea perceptibly 

Fig. 25. 



the rectus. Besides, these two movements are produced in the opposite 
direction for the two muscles. 1 

Our ophthalmotrope fulfils still another purpose. The posterior surface 
of the front half of the vertical meridian is painted in red . 

This red line corresponds to the false image in the case of a paralysis of 
the muscle, the physiological action of which is shown by the ophthalmo¬ 


In fact, as we have just shown, a muscle being paralyzed, the eye takes 
a position exactly the reverse of that which the same muscle, unparalyzed, 
would have given it. The retinal image is, on the other hand, projected 
in the sense opposite to the pathological position of the eye. The false 
image, therefore, corresponds in every way to the physiological action of 
the muscle. 

For example, the superior oblique turns the eye downward and outward , 
and inclines the upper extremity of the vertical meridian towards the nose . 
In case of paralysis of this muscle, the eye is deviated upward and in¬ 
ward , and its vertical meridian is inclined toivards the temple . The conse¬ 
quent false image is inferior , temporal (homonymous diplopia), and inclined 
towards the nose . 

The red meridian , therefore, of the ophthalmotrope is identical with the 
red lines by which, in the preceding pages, we have indicated the image of 
the paralytic eye. 

In fact, these lines are not approximately drawn, as has been the case 
hitherto, but are mathematically correct. 

In Fig. 25, the ophthalmotrope represents the right eye under the in¬ 
fluence of the superior oblique (cornea directed downward and outward; 
vertical meridian inclined towards the nose). 

When unscrewed from the support and fix^Wfy' its opposite end (S), it 
represents the left eye under the influence^^he opposite muscle, the in¬ 
ferior oblique, in our example. 

The side of the eye (right or lefif^S^ the axes of the different pairs 
of muscles, are engraved upon th$*rmgs of the instrument. 

In order to avoid confusionTwfferent colors have been given to the 
different axes of the eye. 

The action of the miiA upon the eyeball can be very simply repre¬ 
sented in still another A^mAer: 

Take an ordij ^'O u bber ball (Fig. 26); draw upon it the cornea, the 
vertical and the RQ^fcontal meridian. On the latter, mark the axis of the 
oblique muscfe©^), 39° from the anterior pole (centre of the cornea), and 
^ ide (R) the axis of the vertical recti, 63° from the pole. 

Bmonstrate the action of, say, the superior oblique , we reason 

This muscle makes all points of the cornea describe parts of 
[el circles around its axis. 


1 Compare Fig. 15 with Fig. 18, and Fig. 16 with Fig. 20. 



Let us now take a compass and open it so that one of its points cor¬ 
responds to this anterior extremity of the muscular axis, for instance 0, 
the other to the centre of the cornea (e). Leaving the former fitfed, we 

Fig. 26. 

Scheme of the right eye. 

draw with the other, upon the ball, the circle of which the centre of the 
cornea describes a part (cO', Fig. 26). 

If we desire to know where this point is situated, for instance, after a 
rotation of 40°, we have only to trace, from the axis (0), as^ne (radius) 
forming an angle of 40° with the horizontal meridian fimpiv* it for the 
superior, above it for the inferior oblique). 

The point where this line touches the circle corresfSpn&s to the centre of 
the cornea after the given rotation. Thus it is cl^a&ly seen how much the 
cornea has turned in the lateral as well as in Mi^yvtical sense. 

As to the direction which the vertical of the eye takes at the 

same time, it is evidently perpendicular to dius 00', and passes through 
the point which the latter has indica^J to us as the centre of the cornea. 
This line is, in fact, no other thainj©) horizontal meridian of the eye in¬ 
clined by the muscular action. iSK^perpendicular to the vertical meridian. 

Thus, in Fig. 26 the twoJWlJ^t oblique tracks indicate the inclination of 
the vertical meridian prodtW®, on the right eye, by the superior oblique 
(O') and the inferior re^^>(12 / ), after a rotation of 40° round their axes. 

On projecting uj vertical lines from the points O' and R' to the 
horizontal meridmn^\0 >/ h and R'h ), we obtain the amount of depression of 
the globe produfc^Vby the muscles in question. 

The permQdiculars O'v and R'v , which are drawn from the points O' 
and R' vertical meridian, correspond to the degree of abduction (O'v), 

causec ^^Dfche oblique, and of adduction (R'v), caused by the rectus muscle. 




What we have said in the foregoing sections concerning the symptoms 
of paralysis of the various muscles of the eye should, it seems to us, be 
sufficient to help the reader to pass in this matter a pretty good examina¬ 
tion. But it is not an examination of this kind to which our patients 
subject us; they do not come with the label of a muscular paralysis, ask¬ 
ing us what were its symptoms; on the contrary, they present to us the 
symptoms from which we are to deduce the paretic or paralyzed muscle 
or muscles. 

Before going farther, we therefore wish to show the reader the method 
which we follow customarily, in order to get our bearings in the multitude 
of complaints to which a muscular paralysis may give rise, to seize, among 
them, the characteristic symptoms, and to reach the desired diagnosis most 
easily and in the surest possible way. 

When a paralysis is complete, it produces a deviation and a limitation 
of the excursions of the eye of such kinds that the simplest examination 
suffices for the discovery of the muscle or muscles which are out of use. 

But paralyses of this sort are not very common; far more frequently 
we meet with paresis. He who should hope to recognize such at the first 
glance, by means of the strabismus which they ought to provoke, would 
expose himself not only to bitter delusions, but also to the gravest misap¬ 

We shall see farther on, when discussing strabometry, that the eyes 
sometimes appear to diverge or converge by virtue ofvthe direction of their 
pupillary axes, while their visual lines, which alo^Adetermine the direction 
of the gaze, may be normally directed, or be d^^ted in the same sense as 
the pupils, or even in the inverse sense. 

Still more deceptive are the differem^^ii height of the eyes. If one 
will direct his attention carefully to tM^Cmatter, it will be found that very 
often one eye is sensibly higher ihantAhe other, in persons who enjoy a 
perfect field of binocular fixatio^ry^Of course in such a case it is not a 
question of the vicious direction of the lines of sight, but of the irregu¬ 
larity of location of the eyj^Jn their orbits, an irregularity or asymmetry 
which, happily, is coi^V^&alanced by the wonderful action of the motor 
apparatus. ^ ^ 

Thus, I discov^^jJ one day accidentally in one of my friends,- a general 
officer, that oneJ^jhis eyes was at least five millimetres higher than the other. 
This nulitariQi^ntleman never has perceived, however, any anomaly in 
his visi^uvapH the attentive examination which he permitted me to make 
provedNdiat both his eyes were emmetropic and enjoyed normal acuteness of 
visimX and that their movements harmonized perfectly in every direction, 
v xWoreover, I have had the opportunity of showing to my pupils a patient 
*ajfected with vertical diplopia. The left eye was visibly lower than the 



right. Hence one might well presume the paresis of a levator muscle of 
that eye, or that of a depressor of its congener. But the examination 
demonstrated that it was a question, on the contrary, of the paresis of the 
superior oblique,—that is to say, of a depressor of the same left eye. Though 
it was below the level of the right eye, the left eye was unquestionably 
directed towards a higher point than that towards which tended the line of 
sight of the other eye. 

It is thus evident to how many errors we should expose ourselves in 
basing upon appearance only our judgment concerning the direction of the 
eyes. In fact, the subjective symptoms of paresis of an ocular muscle are 
much more significant than the exterior aspect of the eyes. 

But here, again, we must not hope that the patient will inform us, at 
the outset, of the diplopia characteristic of the paralysis of each ocular 
muscle. It even happens that a patient may complain of double sight, 
when his muscles are performing their functions quite normally. In such 
a case we are concerned with monocular diplopia , which may have various 
causes entirely independent of the motor apparatus. 

On the other hand, persons who are victims of muscular paralysis are 
often unaware of their diplopia. They say that their vision is dull , but not 
that it is double . The most frequent symptoms of muscular paralysis are 
rather a feeling of extreme annoyance, of pain in the head, of difficulty in 
getting about, vertigo, or an indefinite malaise, which may go to the extent 
of vomiting, etc. 

Very often, also, the gait of such patients betrays their infirmity, and 
he who follows our advice to observe the patient at a distance and in his 
entire behavior will discover a multitude of most precious $igns for the 
diagnosis, which signs will escape him who fixes his attaafwta, from the 
outset, upon the eye which appears to him to be affectecUNp 

Thus, persons afflicted with muscular paralysis/*aSe generally distin¬ 
guishable by an uncertain gait They sometimes 25em dazzled, or as if 
they were afraid of jostling against objects about them. They rarely walk 
with the head straight, and, if they are seafj^lm front of us, they almost 
always look at us more or less obliquely; Q|en, too, they close one eye in 
order to see well, and only then seem ej®j’ely calm and satisfied. 

Insist, then, upon the patient onepitf^ both his eyes, and get him to go 
to the other end of the room and^wirn rapidly towards you. Observe if 
he does not stagger as if th#rv\Ose for liquor; if one side of the body is 
not in advance of the other ^4ie walks; if he does not look at you over 
one shoulder; if he does^Q tip the head backward or forward, or turn it 
towards the right left. Such are the symptoms which not only 

cause you to susn^rehe presence of a muscular paresis, but often even put 
you in the way oryjlnding the muscle affected. 

The patmi^Njffio turns his face towards the left , in order to look at you, 

t, Manual of the Examination of the Eyes, Philadelphia, 1879, p. 21. 



. vVl 


is probably affected in his left external or his right internal rectus; while 
one of the opposite muscles would be likely to be defective in the case of 
him who looks at you with his face turned towards the right.—A head 
inclined backward (nose in the air) gives rise to the presumption of a paresis 
of a levator; a bowed head (forehead most advanced) is likely to indicate 
a paresis of a depressor.—A head leaning to one shoulder ought to awaken 
the suspicion of paralysis of one of the muscles which turn the eye around 
the antero-posterior axis,—in other words, incline the vertical meridian . 

After having thus informed yourself as to the position of the body and 
head, and what seems to help the patient’s vision most, then do the oppo¬ 
site. Place the patient in front of you, his head quite straight, and make 
him open both his eyes. Without attaching too much importance to an 
apparent deviation under such circumstauces, it is nevertheless permissible 
to take cognizance of it. But a truly pathological deviation will be mani¬ 
fest only when, making him fix some object, we cover and uncover the eyes 
alternately . Thus it is that we may assure ourselves whether both eyes are 
simultaneously directed towards the same point, or whether, when excluded 
from vision, they deviate, and in which sense. 

Remark especially if the deviation is the same for both eyes , or if it is 
more pronounced in one than in the other . This phenomenon is, as w^e have 
previously shown, pathognomonic of a muscular paralysis, and indicates, 
at the same time, which eye is affected. The paralyzed eye is that which 
deviates less . 

As fixation-object the index finger, held in the median line before the 
patient, is customarily chosen. This simple method is not altogether bad, 
but it could be better. The finger, held near the patpa’s nose, obliges him 
to converge. Now, if he is the victim of conver^^strabismus, the direc¬ 
tion which we force him to give to his eyes for us, at least in part, 

his real infirmity, which would become mw3w more apparent if he were 
looking at a distant object, because such dS&mt vision calls for parallelism 
of the visual lines. 

Hence we advise that the distaii^ of the fixation-object be varied ; that 
it be at first a near object, then Qlistant object.—But what is especially 
important is that the directu the object fixed be varied. The finger 
should be moved to the lefyw)the right, up, down, or, again, the direction 
of the patient’s gaze is ^§e varied, as we shall see, by changing the direc¬ 
tion of his head, O 

This summarv inspection having been carefully made, have recourse to 
a symptom wlmSOis much more important and much more apt to fix the 
diagnosis,is to say, to the diplopia . It will never be lacking, pro¬ 
vided da^yinocular vision has existed before the malady, and that one 
knows Im^ to provoke it. 

wSSAprder to produce diplopia, we use as fixation-object a candle flame 
Mium stands out boldly upon a dark background. We place it at a distance 
iybr at least two metres, in order that the separation of the two images^ may 



be notable enough for a deviation of even a few degrees. We cover one of 
the patient’s eyes—generally the one which has the better visual acuity— 
with a colored glass. It is best to choose a red glass of not too deep a 
shade. This changes the color of the flame sufficiently to distinguish it 
from that seen by the other eye, but does not deprive it of so much lumi¬ 
nous intensity that the patient may fail to perceive it. 

Then the patient opens both eyes and holds his head erect and motion¬ 
less, and we ask him if he sees one light or two lights? If he admits only 
one, we ask him the color of it, and we cover, for an instant, the eye with 
which he sees it, in order to attract his attention to the image received 
by the other eye. In this way, one generally succeeds readily enough in 
rendering the diplopia manifest. If not, the direction of the gaze is to be 
varied, for it might happen that the defect in motility would be weak enough 
not to interfere with binocular vision while the patient is looking straight 
ahead, but only for certain directions of the eyes. We know, indeed, that 
diplopia manifests itself especially in the direction towards which the 
enfeebled muscle turns the eye. 

On the other hand, it has been observed that pathological convergence 
has a tendency to increase when the gaze is downward , while divergent 
strabismus is especially shown when the patient looks upward . This pecu¬ 
liarity is probably due to the fact that it is generally in order to observe 
near objects, which necessitates an effort of convergence, that we look down¬ 
ward ; while we direct the gaze upward to look at infinite distance, to relax 
our adductor muscles and abandon the eyes to the abductors. 

In order to change the direction of the gaze, it is customary to displace 
the fixation-object. A simpler and better method is to leawe the flame 
where it is, and to change the direction of the patient’s head^W^ us, in order 
to make him look upward, we direct his face downward j(^porder to make 
him look downward, we direct his face upward; in or$pV) make him look 
towards the right or the left, we turn his face to^^ left or to the right, 
and the same for intermediate directions. In thkjQay, not only do we avoid 
promenades with the lighted candle, not we always control the 

position of the patient’s head, but we do a^tay with a cause of error which 
has led more than one master astray. ^ 

It happens, indeed, at times, th&cMhe patient, instead of seeing the 
images separated horizontally illy, declares that one of them comes 

towards him. He then loses ^WMiotion as to the relative distance of the 
two images. This fact is c^aple of easy explanation, as follows: 

Let Fig. 27, ABCVgfae our consultation-room, P the patient’s head, 
F the candle flame, pl^yfei against the wall opposite him. 

If he has parjffomb of the left external rectus , he will see this flame at F 
with his right e^^&nd a second flame at F f with the left eye. 

If now w^Varry the flame from F to #, the separation of the two flames 
increases^JiQ) the patient ought to see one flame at $ and the other at Q ', 
as if it behind the wall AB of the room. It is true that the image of 


naturally colored light), ^ will answer, “ It is nearer” (lie referring to 
himself). ~ 

Even if we suc^gj 1 in rendering our question comprehensible to the 
patient, it is som^fi^es very difficult to establish whether the separation be¬ 
tween the two ©iges is increased or diminished, inasmuch as the patient is 
often decqK^Sy in such a case, and even declares that the two images are 
nearer eaS^ther, when they notoriously are farther apart. 

TtaXsame thing occurs for the vertical diplopia when the object of 
fixatmn is raised or lowered. 



et us, for instance, turn Fig. 27 ninety degrees to the left. Then AB 





will represent the floor and CD the ceiling of the consultation-room. In¬ 
stead of supposing that one of the flames is lowered into the cellar at the 
patient, subject to paralysis of a depressor, supposes that it is advanced 
towards him, on the floor, to 

We put an end to all these embarrassments in changing the direction of 
the gaze by altering that of the patient’s head . In order to cause him to look 
towards the left, we turn his head (that is to say, his face) towards the 
right. To make him look to the right, we direct the face towards the left. 
To turn his gaze upward, we incline the face downward, and to lower the 
gaze, we direct the face upward. In this way, the plane of projection of 
the double images always remains the same. It is the wall on the surface 
of which is placed the flame. 

Diplopia having been obtained, we first take into account in what sense 
it is produced, whether in the horizontal, the vertical, or in both directions 
at once; if it be homonymous or crossed, vertical or intermediate. 1 

After having informed ourselves concerning the diplopia, while the 
patient is looking straight ahead, we change the direction of the gaze (by 
means of movements of the head), asking him if the two images separate 
or if they approach each other. 

We thus find, at once, not only which is the affected eye, but also the 
direction of the action of the implicated muscle,—indeed, even the muscle 
itself, when it is a question of one of the lateral recti. 

In fact, the affected eye is that in the direction of the image of which the 
diplopia increases, and the paretic muscle is that which turns the eye in the 
sense of the false image . 


The left eye being covered with a red glass, the patient apM*nces homony¬ 
mous diplopia; the left eye’s image is to the left, that ofVt^Pright eye to the 
right. We direct the patient’s gaze towards the lef^^ turning his head 
towards the right. If the double images get fartj^^apart, it is the left eye 
which is the affected one, because it is in the of its image that the 

diplopia increases, and it is its external rectos wmcli is affected, for it is that 
muscle which directs the eye towards 10* false image,—that is to say, 
towards the left. 

If there be crossed diplopia, thawed) image belonging to the left eye is 
at the right , that belonging to eye is at the left . If then the di- 

plopia increases when the g^fte^^uirected towards the left , it is the right eye 

1 It is to be noticed tha^ tj^jwtient sometimes speaks of a certain difference in the level 
of the double images as ace^^mnying a horizontal diplopia. This is often due to an un¬ 
conscious inclination ofArfiLiead, or to the fact that an eye which is subject to a very pro¬ 
nounced convergei^^^bismus usually deviates slightly upward, while high degrees of 
divergence are rejfc^Jfcombined with a certain lowering of the eye. One can then bring 
the two images to^cK^o the same level by rectifying the position of the patient’s head. 

There to suspect a complication with the paresis of a muscle acting ver¬ 

tically o^y wen the difference in height does not admit of so simple correction, and 
especialb^^hen it is more marked than the horizontal diplopia. 



which is the affected one, inasmuch as, this time, it is its image which is 
at the left. Moreover, we shall know that we are concerned with paresis 
of the internal rectus , because it is that muscle which turns the right eye 
towards the left. 

Let us now take the case of a vertical diplopia: the two images are 
superposed . This case is a rather complicated one, inasmuch as there are no 
less than eight muscles whose paralysis may provoke this phenomenon. 
But with the aid of our law we easily regain our bearings. 

The left eye being still covered by the red glass, we ask the patient 
whether the red flame is above or below the other. 

Suppose the patient answers that it is below. If now, in lowering the 
gaze, the images separate still farther, we shall know that it is a question 
of the paralysis of a depressor of the left eye. If they approach each 
other, it is one of the levators of the right eye which is paretic. Indeed, 
if, on the contrary, we make the patient look upward in order to see the 
fixation-object, the diplopia is increased. It increases in the direction of 
the higher image,—that is to say, that of the right eye. 

But suppose we are concerned with paresis of a depressor of the left eye. 
It remains for us to determine whether it be the inferior rectus or the 
superior oblique which is paretic. 

We bear in mind that the former is, at the same time, an adductor , and 
that, in consequence, its paralysis must bring about, besides the raising of 
the eye, a divergent strabismus with crossed diplopia , while paralysis of the 
superior oblique has convergence and homonymous diplopia as its accompa¬ 

We therefore ask the patient if the two flames tli^t he sees are exactly 
in the same vertical, or if one of them is a little right or left of the 

other. If he answers this question clearly, ouruMgnosis is complete. But 
very often this horizontal deviation is not marked, or the patient is 
not sufficiently aware of it; his answers undecided and ill adapted to 
inform us concerning the exact positioB^Dthe deviated eye. 

We might then think of havingV^ourse to a third rotation that an 
eye whose depressor is paralyzed jpoergoes, the rotation around the antero¬ 
posterior axis, the inclination oiyttie vertical meridian , which is nasal for the 
rectus muscle, temporal for t l^wolique. But if the patient be not aware of 
the horizontal separatiqtoAjap tne two images he will habitually recognize 
still less the obliquhy ^fvbne of them. 

Hence one wou^l^be much embarrassed to make a diagnosis in such 
a case, if thereiS^re not some means for rendering the character of the 
diplopia mor^M^ar and apparent. This means consists again in the varia¬ 
tion of t&CHjrection of the gaze. 

Dir^Jfe he patient’s face to the left, so that he is obliged to turn his eyes 
toivanqs the right in order to see the object. If, in this case, the difference 
\ftt of the double images diminishes , while a certain degree of crossed 
lopia , and, especially, an inclination of the lower image towards the 



temple , is manifested , we have to do with paresis of the inferior rectus. 
(See page 25.)—The inverse will occur, when the gaze is towards the 
left, the direction of the face towards the right in our example. 

On the contrary, increase of the vertical separation , when the eyes are 
directed to the right (in our example), diminution of the difference in height , 
when the gaze is to the left , with apparition of increasing nasal obliquity , 
characterize paresis of the superior oblique. 

There is a very easy means of recalling instantaneously the variation 
which the diplopia caused by paralysis of a depressor or levator undergoes 
in the different directions of the gaze. One needs only to remember the. 
direction of the muscles , and to say that the more the gaze (the axis of the 
eye) approaches this direction , the more the action of the muscle in the ver¬ 
tical (lowering or raising) becomes manifest; and that, on the contrary, the 
more the eye deviates from the direction of the muscle , the more the latter 
becomes a rotator around the antero-posterior axis, the more the inclination 
of the meridian becomes manifest. 

The recti muscles (superior and inferior) are directed towards the temple. 
Consequently an increase in the vertical diplopia , when the patient looks 
towards the temple of the affected side, indicates the paralysis of a rectus 
muscle. In order to make the diagnosis still more certain, the patient will 
be required to look in the opposite direction, and the obliquity of one of the 
images will be manifested, at the same time that the difference in height 
will diminish. 

The oblique muscles may be considered as being directed towards the 
nose. Hence, if the vertical diplopia is increased when the patient directs 
the paralyzed eye towards the nose , it is one of the oblique ^Auscles which 
is affected.—Inversely, the double images come closer to eat*Ko9ier, and the 
obliquity of one of them increases , when the gaze is tow/ds the temple of 
the affected side. JO 

The patient’s appreciation of the obliquity ofXpe of these images may 
sometimes give rise to an error. On lookiiMp&Jhe left, he will, perhaps, 
be clearly aware of their mutual approacl^arad^of the obliquity of one of 
them. We are then much gratified to st^ the perfect concordance of the 
ascertained symptoms with what we hg^p foreseen ; but, when we say to the 

patient, “ Of course the lower flar^e^eans towards the right?” “Not at 
all,” he objects; “ the lower perfectly upright; it is the upper one, 

which leans towards the lgf(?^-Now, the upper image belongs to the 
right eye, which, up to thfl^tjlne, we have regarded as healthy. Have we 
deceived ourselves as eye, or is there some complication on the part 

of the right eye,—so^^paresis, some contraction ? No; the appreciation 
of the inclinatimjMOl line depends on what one regards as the vertical; 
in our exampl^ the two flames lean towards each other. If the patient 
bases his obs^Wation upon that which belongs to the right eye, in order to 
appreci^b^Qiennclination of the other, he will say, as we had hoped, that 
the lm^g^flame leans towards the right. If, on the contrary, he takes as 



standard the lower light, it is the other one which is not upright, but whose 
upper extremity leans towards the left. 

It is as if, in a case of paralysis of the left abductor, this eye being cov¬ 
ered with a red glass, we ask him, “ The red flame is to the left, the yellow 
to the right, isn’t it?” and he answers, “No, the yellow is in the middle 
and the red is to the left;” or, again, “ The red is in the middle and the 
yellow to the right.” It is simply a question of personal appreciation. 

The examples cited will suffice to enable the reader to apply efficaciously 
the theories brought out in the preceding paragraphs, and to succeed, even 
with patients of defective intelligence, in reaching a precise diagnosis of 
every muscular paresis or paralysis. 

The attentive clinician will find then, to his great satisfaction, that the 
so-called complicated, obscure cases that do not fall in with the laws of 
physiology are of very rare occurrence. For our part, we have never yet 
met an “ obscure” case in which some lack of attention on our part or on 
that of the patient was not infinitely more probable than any defect in the 
laws of physiology, whence those of pathology are necessarily and logically 



In order to become fully acquainted with a case of strabismus, it is 
necessary to determine the degree of it; to add to its qualitative, so to say, 
its quantitative analysis. 

Strabometry is the name we give to this detailed analysis of an ocular 
deviation. It comprises the determination of the degree of the deviation 
—that is to say, of the angle of strabismus —and the examination of the 
monocular and binocular excursions, of the monocular,fields of fixation, 
well as of the binocular field, of fixation. ^ 


We have given to the angle of stra-^smus the following definition : 
the angle of the strabismus is the angl<fcbm$riscd between the direction which 
the line of sight of an eye has and tftyt/imich it ought to have} 

The simplest method for solQ^ig this problem objectively is the fol¬ 
lowing : 2 

The deviated eye is pitted kt the centre of a semicircle, movable about 
its summit, which sumrb^is at the same time the zero-point of a divi¬ 
sion which goes, or^TijWr side, to 90°. Our perimeter is well adapted to 
this use; its arc (PfrP, Fig. 28) is placed in the plane of the deviation 
of the eye, honwjStal for lateral strabismus, vertical for vertical strabis¬ 
mus, obliqurf^for intermediate strabismus, unless one prefers to divide 
the latt^K^h of squint into two components, the one horizontal and the 


1 iQdolt, GraefeundSaemisch, Handbuch der gesammten Augenkeilkunde, iii. S. 325. 

t is based upon a principle pointed out by M. Javal. 



Fig. 28. 


6 $ 

The patient is. made to fix the point 0 (Fig. 28) situated in the pro¬ 
longation of the radius of the arc, which passes through its summit o. 
In order to avoid the error 
which might result from con¬ 
vergence, we select, for an 
object of fixation, one as far 
distant as possible, at least 
five metres away. 

The sound eye (D) alone 
will be directed towards the 
object. If the affected eye 
(6r) were equally so, its line 
of sight would necessarily 
pass through the point o of 
the arc. Hence GoO is the 
direction which the eye ought 
to have. But as it is, in 
reality, deviated, its line of 
sight passes through some 
other point of the arc. The 
corresponding division x will 
give us the angle of the stra¬ 
bismus, oGx. How is this 
point x to be determined ? 

If the line of sight passed 
through a known and visible 
point of the globe, nothing 
would be easier than to ascer¬ 
tain, objectively , its direction. 

But such is not the case; we 
can only presume that it does 
not pass far from the centre 
of the pupil. 

Hence, for an approxi¬ 
mate appreciation, we simply 
seek the point of the peri¬ 
metric arc towards which ig ^fffected the ray of the cornea which passes 
through the pupillary cental 

For that purpose, w^move, along the inner surface of the arc, a small 
lighted candle, F 2o), whose movement we follow with one of our 

eyes, d (the othe^V^bag closed), in such a way that our eye and the flame 
are always on^h^ same radius of the perimeter. The point of the arc 
where the cradle must be placed, in order that its reflex shall appear 
just at^th^jefitre of the pupil of the observed eye, is then that towards 
radius of the cornea which passes through the pupillary centre is 

Carl F. Shepard Wsmorial Library 
Illinois cf Optometry 

3241 S. Arkh^cn Ave. 

Chicago, HI. 60616 1*4^5 


point; | 


strabometrv. — PoP, perimeter arc; o, its zero- 
fleet of fixation; (?, the patient’s eye deviated 
\ d , the observer’s eye. 




directed. For simplicity’s sake, we will call this the pupillary axis, and 
the degree on the arc designates what I call the apparent strabismus. l 

One may be content with the degree of the apparent strabismus when 
it is not a question of great precision, or in the case of amaurosis of the 
deviated eye, for when there is no vision there is no visual line. 

But when one wishes to know the real strabismus , the degree of the 
deviation of the visual line, then it is necessary also to determine the angle 
separating the pupillary axis from the visual line. I have given to this 
angle the sign x and the name Kappa. 2 

Fig. 29. 

The angle Kappa may be determined, with sufficient precision for prac¬ 
tice, in the following way: The affected eye being placed at the centre of 
the perimeter, we cover the sound eye, and hav^ffi^atient fix the flame 
at the summit of the arc. In this case the visual line is necessarily di¬ 
rected towards this zero-point, 0 (Fig. 29).^^ the visual line coincided 
with the pupillary axis, the reflex of the^^ae would appear to be at the 
centre of the pupil, when we look at observed eye from the summit of 
the arc. This may occur, but it is RQ^/tne rule ; in general, the pupillary 
axis passes to the outside or to theX^side of the visual line. 

To find at once the directmnNand the degree of the angle Kappa, we 
leave the flame immobile qj^Sfe zero-point, and we move our eye along 
the arc until we have *tne point at which it is necessary to view the 

observed eye in orderwht the reflex of the flame may appear at the 
centre of the pupil^JTne corresponding degree on the arc then represents 
tioice the angle* Bjtppa. 



1 It ha& k£(^Sought to base such researches upon the centre of the cornea. But, aside 
from thalsm^fenat the centre of the cornea is more difficult to find than that of the pupil, 
it is in n<NJ^se the cornea, but the pupil, which determines, for the observer, the direction 
of thesftize of an eye, and, consequently, the apparent strabismus. 

adolt, Traite complet d’Ophthalmologie, par De Wecker et Landolt, iii., p. 815, 



The explanation of this is very simple: Let fO (Fig. 29) be the visual 
line of the eye, XP the pupillary axis. OXP will be the angle Kappa. 
If the flame remain at 0 , I am obliged to move my eye to P' in order to 
see, at the centre of the pupil, its reflex formed by the portion C of the 
cornea. Now, the angle OCP' represents the sum of the angle of inci¬ 
dence OOP and the angle of reflection PCP which are equal. The angle 
of incidence OCP, being nearly equal to the angle Kappa, may be regarded 
as the double of the angle Kappa. 

It might seem that it would be simpler to have the patient fix the zero- 
point of the arc, and to carry the candle along the arc, in order to find, at 
P, directly, the angle Kappa. But this angle is usually so small that we 
are glad to possess, for its rapid determination, a method which gives a 
precision double that of this direct method. 

Usually the pupillary axis passes without —that is to say, at the temporal 
side 0 f—the visual line {positive angle Kappa, +*). This condition pro¬ 
duces for the spectator (who has for his guide only the pupils which he 
sees, and not the visual lines which he does not see) the appearance of a 
divergent strabismus f even when the eyes of the person observed are nor¬ 
mally directed. Thus, in case of positive angle Kappa, a real divergence 
appears exaggerated, while a convergent strabismus is apparently dimin¬ 
ished—indeed, often entirely concealed. 

To find the real angle of strabismus it is, therefore, necessary to subtract 
the positive angle Kappa from the apparent divergent strabismus, and to add 
it to the apparent convergent strabismus. 

The angle Kappa takes the negative sign (—%) when the pupillary axis 
passes to the inside —to the nasal side—of the visual line. Tn this case 
there is an apparent convergence during the normal direc^rbqf the gaze. 
Hence the negative angle Kappa ought to be added tqrate angle of the 
apparent divergent strabismus, inasmuch as the lines ^rf^&ight diverge even 
when the eyes have the appearance of being parajlfl^r It ought to be sub¬ 
tracted from the angle of the apparent cori'yer^e^i^^bismus, which it causes 
to appear unduly great. 


The diplopia which we have one of the principal symptoms 

of paralytic strabismus permits i»S^determine the angle of strabismus 
much more easily and exactly tm^Joy the preceding method. 

The plan of subjective dfrabemetry that we have pointed out 1 is based 
on the fact that the distanp^rbetween the double images is the tangent of the 
angle of strabismus . 

We need only rai^to Fig. 2, in which 0 is the fixation-object, £ the 
point towards the deviated eye is directed, and Omi 2 the angle of 

strabismus. * 


1 LandS^^^Atfnales d’oculistique, Juillet, 1875. 
Ophthalmology, iy., September, 1875. 

See also Hirschberg, in Archives of 



In order to find the point 0' where the deviated eye supposes the object 
0 to be, we have been obliged to bring this eye back to its normal direction, 
to make it execute a rotation equal to its angle of strabismus in the inverse 
sense. Hence the angle OmO' is equal to the angle of deviation Omtt ; the 
distance separating the two images, 0 , seen by the healthy eye, and O', seen 
by the affected eye, is, therefore, the tangent as well of the angle OmO' as 
of the angle of strabismus. 

It suffices to measure this distance as well as that which separates 
the eye from the object of fixation, to obtain the angle of deviation,—in 
other words, the angle of strabismus,—by means of a simple trigonometric 

To avoid any calculation, we have divided into tangents of multiples 
of 5° one of the walls of our consultation^room. This division is, of 
course, applicable to only one radius,—that is to say, to a given distance. 
It is therefore necessary that the person examined shall always occupy 
the same position relatively to the wall. For that purpose, we have 
marked, by four nails driven into the floor, the location of the chair 
occupied by the patient. On the wall opposite to him, on a level with his 
eyes, is the zero-point of our division, which goes from there to the right, 
to the left, upward and downward, and in two intermediate directions. 
The patient is, so to say, within a sphere whose centre coincides with his 
eyes, while the points where the radii, going thence, reach the wall, are 
designated by figures. 

If we place, on the wall, a candle flame at the zero-point of the divi¬ 
sion, the patient needs only to point out the place at which he sees the 
second image, and we read there directly the angle of his strabismus. We 
may similarly appreciate the increase and the diitfhmtion of this angle in 
the different directions of the gaze. 

For a distance of three metres, the tangenteQscnat is to say, the divisions 
of the wall—are the following : v 

Starting from the zero-point, 

5° = 26 cm. 
10° = 53 cm. 
15° = 80 cm. 

The upper part of 
convenient, however,^ 

'9 cm. 
140 cm. 
= 173 cm. 

35° = 210 cm. 
40° = 251 cm. 
45° = 300 cm. 

tical meridian bears the same division, 
bntinue it further, and to mark 

It is 

58 cm. 

55° =■ 428 cm. 

The Jow^qiart is divided in the same way as far as to the floor. 
Tl^j&iter will be found eleven centimetres below the number 20° of 
the chvmon. 

^$qpm this point (120 cm. from the zero-point) the degrees of the 
^iwision present the following distances: 


25° = 43 cm. 
30° = 92 cm. 
35° = 129 cm. 

40° = 157 cm. 
45° == 180 cm. 
50° = 200 cm. 

55° = 216 cm. 
60° = 231 cm. 

For a radius of two hundred and twenty-jive centimetres (tlie distance 

from the patient to the wall) the divisions of the horizontal meridian cor¬ 
respond to the following numbers : 

Starting from the zero-point, 

20° = 82 cm. 
25° = 105 cm. 
30° = 130 cm. 

5° = 19.6 cm. 
10° = 39.6 cm. 
15° = 60 cm. 

35° = 158 cm. 
40° = 189 cm. 
45° = 225 cm. 

For the ascending part of the vertical meridian, 

50° = 274 cm. 

55° = 321 cm. 

The descending part touches the floor at one hundred and twenty cen¬ 
timetres,—that is to say, between 25° and 30°. 

From this point (120 cm. from the zero-point) the different degrees 
correspond to the following lengths: 

30° = 18 cm. 
35° =--= 54 cm. 

45° = 105 cm. 
50° = 124 cm. 

55° = 141 cm. 
60° = 156 cm. 

A prismatic glass deflects towards its base 
the luminous rays which traverse it, in such 

Fig. 30. 

a way that, to an eye looking through it, 
objects appear displaced towards the summit 
of the prism. 

Thus, in Fig. 30, the ray OP, which 
comes from the luminous point 0, instead of 
continuing its course in a straight Hi 
wards o, is, by the prism BAB, de 

towards /,—that is to sav, towards the bas 
BB of the prism,—as if it came fronxJd 

point fSO 

Thus oPf is the angle of of 

the prism. This angle is equaUjxfehe angle 
OPli, since Po is the prolongation of OP, 
as PQ is that of fP. . 

This property of pw**J? may be utilized 
to direct upon theds^^rcentralis of a devi¬ 
ated eye the lunitA^vis : rays which would not 
otherwise reach «tN 

Thus, if^fojp eye in our figure be directed 
towards i^uistead of being directed towards 



0, the prism BAB will cause to fall on the fovea centralis / the image of 
0, which otherwise would be formed upon an excentric point (o) of the 

Now, if 0 is the object fixed by the sound eye, and 9 the point towards 
which the strabotic eye is directed, 0P9 is the angle of strabismus , and 
that angle is equal to the angle of deviation of the prism BAB. 

This prism is called the correcting prism ; for, by causing the image of 
the fixation-object to fall upon the fovea centralis of the affected eye, it 
brings about the fusion of the two images, it puts an end to the diplopia, 
and corrects, so to say, the strabismus. 

Hence the correcting prism also gives the measure of the strabismus. 
That is one of the reasons why it seems logical to us to inscribe upon the 
prism the angle of the deviation which it produces. The diplopia corrected 
by prism No. 10 will indicate, then, a strabismus of 10°. And if we have 
ascertained, by some other method, the angle of a strabismus,—an angle of 
8°, for instance,—we shall know that it is corrected by prism No. 8. 1 

It is true that, since the Washington Congress, two other propositions as to the method 
of numbering prisms have been made. The first is that of Dr. Dennett, 2 who would take 
as a limit of measurement of prismatic refraction the tenth of the radian , which he calls 
“centrad.” The other proposition comes from Mr. Prentice. 3 This author would take as 
the measure of a prism the tangent of the deviation for a radius of one metre. His unit 
is a prism which at this distance produces an apparent displacement of one centimetre: 
he calls it the “ prism dioptre .’ 1 

This is not the place in which to enter into the discussion of these two methods, both 
of which are very ingenious. Their advantages are pointed out by their authors in the 
publications cited. In spite of that, and notwithstanding a most flattering letter which 
the American Ophthalmological Society has done me the hojior to address to me, by its 
eminent Secretary, Dr. Samuel B. St. John, 4 in favor of#S^anett’s system (a letter to 

uVl nn 

which I am happy to make here a respectful response). 

Ind it more practical and 

1 Up to the present, prisms have been number^ 
(BAB, Fig. 30). This principle of the numberi 
tical; for the angle of opening scarcely interop 
This action, with 

action of the prism. 

Scording to their angle of opening 
prisms is neither logical nor prac- 
T, as it does not indicate the deflective 
lone we are concerned, depends, indeed, 


not merely upon the angle of the prism, buMilso upon the material of which it is made. 
The angle of deviation of a prism is one-half of its angle of opening, in the case of 

ordinary spectacle glass. It increase&Jmd decreases with the index of refraction of the 

It was in order to obviajAmjs inconvenience, and to facilitate, for the oculist, the 
employment of prisms in^A^Jbasurement as well as in the correction of the motor troubles 
of the eye, that the se<^o|Mn Ophthalmology of the International Congress of Medicr.l 
Sciences at Washinj/um|fre87) charged Drs. Edward Jackson, Swan M. Burnett, and my¬ 
self to propose to tncNText International Congress to number prismatic glasses according 
to the angle ofl^^pdeviation which they produce. I acquitted myself of this mission at 
the Internati^ar Ophthalmological Congress at Heidelberg in 1888, as well as at that of 
MedicaM^Qbces at Berlin in 1890, and I have not ceased to do my best to further this 
useful^^sjhi. See also E. Maddox, Journal of Anat. and Physiol., xxi. p. 32. 

^ William S. Dennett, Transactions of the American Ophthalmological Society, 1890. 
v ^4charles F. Prentice, The Metric System of Numbering and Measuring Prisms, 
^ A^ehiwes of Ophthalmology, iii., 1890. 

4 July, 1890. 



simple to number the prisms according to their angle of deviation , just as in strabometry, 
in measuring the excursions of the eyes, in designating the angles Kappa, Alpha, Gamma, 

The centrad may have its advantages in physics, but physicists have not yet adopted 
it. How could we assume this reform, we who have only distant relations with the exact 
sciences? This reform, in order to be logical, would include, moreover, a considerable 
change in the graduation of all our apparatus and instruments—perimeter, ophthal¬ 
mometer, etc., all divided in degrees. 

Strabometry with the aid of prisms is, as we have pointed out., 1 subject 
to a slight error. The correcting prism may prove to be a shade weaker 
than the angle of strabismus. This fact is explicable in the following 
way. When a prism has brought the double images to within a short dis¬ 
tance of each other, the tendency to binocular and single vision is power¬ 
fully awakened and provokes a most energetic contraction of the paretic 
muscle in order to realize the fusion of the two images. The instinctive 
feeling of the impossibility of attaining fusion prevents the patient from 
making that effort while the diplopia is still too great. 

The same fact shows itself also in a very striking way in Fig. 7. The curve, which 
represents the diplopia of a person affected with paresis of the left external rectus, is regu¬ 
lar up to the thirty-fifth degree at the right. There, it descends suddenly, to become fused 
with the horizontal line. Thjs means that the separation between the double images, having 
diminished gradually during the gaze towards the healthy side, becomes suddenly nil , as 
soon as the images are so near to each other that a slight effort of the paretic muscle 
suffices to bring about their fusion. 

In order to avoid this error, one need only choose, as correcting prism, 
that prism which causes and maintains, without effort, the fusion of the 
double images. aA 

The three methods of strabometry—first, by means of t mwrneal reflex ; 
second, by means of tangents ; and, third, by means of —are the most 

rational and most practical ones with which we are ac/ffipinted. Being each 
based upon a principle differing from that of the^^hers, but all tending to 
the same end,—the determination of the an$e\m the strabismus,—they 
exercise an excellent control over each othe^^jrfence we recommend them 
to all who wish to determine the degree of^^bviation of an eye with a pre¬ 
cision sufficient and easy to obtain injustice. 

These methods of strabometry^V^rational, because they measure the 
angle of the deviation of the eyft^Sjfu express it in degrees . 

It is incomprehensible that kny one should ever have attempted to 
express a deviation, a rotartaw of the eye,—that is to say, an essentially 
angular value,—by liitoj^Jmeasures. Nevertheless, we still hear of a 
strabismus of so mmjX^nllimetres or lines, as if the eye, that has turned 
aiound its centre^J^mtation, had been displaced along a line. This is quite 
as absurd as ifi^e should wish to express exophthalmia or any other dis¬ 
placement eye by means of angular degrees. 

L Landolt, De la Strabometrie, Annales d’oeulistique, 1875. 


Indeed, logical in this lack of logic, the author of one of the principal 

works on this subject has substituted millimetres for the angle of strabis¬ 
mus and expresses the difference of the level of the eyes by degrees. Let 
us hope that the future generation will do justice to these aberrations which 
we have never ceased to combat. 1 


The degree of the deviation does not suffice to give a correct idea of 
the strabismus; we must further know the field of excursion, or field of 
fixation , of each of the eyes. This is true not only for paralyses of the 
ocular muscles, but still more for non-paralytic strabismus, with which we 
shall later become acquainted. 

The field of fixation is most simply determined by aid of the perime¬ 
ter, at the centre of which is placed the eye to be examined, the other 
being covered by a bandage. The eye is made to follow a fixation-object 
(letter, figure, printed word, or the like) which is moved, in all directions, 
along the arc of the perimeter. The degrees at which the object ceases 
to be seen distinctly, correspond to the limits of the excursions of the eye. 
These degrees may be inscribed on the same scheme as is used for the field 
of indirect vision. Their union gives the field of fixation. (See Figs. 
12, 14, 19, 21, 22, 23, and 24.) 

In order that this somewhat primitive experiment may be sufficiently 
exact for practice, it is necessary that the patient’s head be immobile, other¬ 
wise its rotations will be added to those of the eye, and vitiate the result 
of our investigation. The head could not be more solidly or more simply 
fixed than by the teeth, which form part of the §Meton. For this pur¬ 
pose we use a horizontal strip of soft wood, sci^><^over the support of our 
perimeter. It is wrapped in a bit of white pap(K)and the patient is directed 
to seize solidly, between his molars, the side or the left side of the 

mouth-piece, according as one wishes tM^eamiue the left or the right eye, 
which thus finds itself at the centrirT*i^ie perimeter. 

Instead of answering by wottls^rnich would cause a relaxation of the 
bit, the patient indicates by si^Tjpmade with his hand, whether or not he 

sees the object distinctly. Jb. . . .. . 

Another precaution isselect fixation-objects of such a kind that the 
patient can distingui^4liem by direct vision only. If, for instance, he 
still read the w *the aid of a part of the retina distant from the 

fovea centralis, th^angle of excentricity would unduly increase the field 
of fixation. 4 ^^wever, this is less to be feared, as a matter of fact, than is 
O' It is noticeable, indeed, that sight decreases in the extreme 
the gaze; in other words, that the object of fixation appears 
en to a normal eye, when the latter approaches the limits of 

^ 1 Snellen und Landolt, Strabometrie, Graefe und Saemisch, Handbuch der gesammten 
^Augenheilkunde, iii. S. 235, 1874. 



its field of fixation. Hence it is desirable to select an object which is 
readily distinguishable, but which, notwithstanding, cannot be recognized 
by indirect vision. 

When the vision of the eye under examination is very feeble, or the 
patient lacks intelligence, the field of excursion is to be determined objec¬ 
tively by the aid of the corneal reflex. A small lighted candle is placed at 
the zero-point of the arc, and the patient is made to fix it. By looking 
above or below the arc, as in strabometry (p. 44), one then places one’s own 
eye so that the reflex of the flame appears just at the centre of the pupil 
of the examined eye. Then one moves the candle along the arc, having 
the patient’s gaze follow it, and accompanies it with one’s own eye until the 
reflex leaves the pupillary centre,—that is to say, until the examined eye 
can no longer follow the object. This point corresponds to the limit of 
the field of excursion. 

The field thus determined is almost always a little more extended than 
the subjective field of fixation. The explanation of this fact is to be found 
in the lessening of sight which we have just pointed out in the extreme 
deviation of the gaze. 

Just as in the case of the angle of strabismus, it is best, in order to be 
exact, to take into account the angle Kappa in the objective mensuration 
of the field of fixation. 


The most important thing to determine in every case of strabismus— 
indeed, in every case of a trouble in the motility of the eyes—is the binoc¬ 
ular field of fixation, the extent of the space over which the l^s of sight 
of the two eyes can meet in the same 
point of fixation. This experiment 
should be made at such a distance that 
the convergence may be disregarded. 

We use for this the mural division 
which we have described in the discus¬ 
sion of subjective strabometry. We 
have marked for this purpose upon 
the wall the tangents of the multi{NS>ol 
pies of 5° in nine meridians, sepa^^Qj^ 
bv 20° from each other, also th^^ri- 
dians inclined at 45°. (See 

The person to be * (Ruined is 
placed before this divi^h in such a 
way that his eye^Qfeespond to the 
centic of the in*^Khry hemisphere whose projection is inscribed on the 
vail and flooi^V Ttie head is fixed by means of a dental strip supported by 
a ?0 ^ Then one moves, along the principal meridians of the 

c art, aft^ited candle, which the patient follows with his eyes until he 

Normal binocular field of fixation. 



commences to see it double. The point at which this diplopia appears con¬ 
stitutes the limit of the field of binocular fixation in each given direction. 

This is recorded, on a scheme like that used for the record of the monocular 

The perception of the diplopia is favored by a colored glass, which is 
best held by the patient himself before one of his eyes. 

The full line in Fig. 31 corresponds to the normal field of binocular 
fixation of the author. The pointed curves at the left and right of the 
lower part of the figure are nothing else than the infero-external limits of 
the monocular fields of fixation. The nose prevents this space from being 
dominated simultaneously by both eyes. 


The affections which are capable of causing paralysis of the motor nerves 
of the eyes are numerous by reason of the long course of these nerves, their 
divers relations with adjacent organs, the relatively considerable extent of 
their central and peripheral expansions, and the multiplicity of the altera¬ 
tions of which these organs and regions are susceptible. 

Following these nerves from their intra-hemispheric origin to their orbital 
termination, four principal groups may be distinguished in the paralyses of 
the motor nerves of the eye: 

First, paralyses from lesions of the intra-cerebral course of these nerves; 
second, paralyses from lesions of their protuber ential nuclei ; third, paralyses 
from lesions of these nerves in their course after their apparent origin,—that 

Here we have to deal only v^htne third and fourth groups,—that is to 
say, with the lesions to which© 1686 nerves are exposed after having left 

lesions to which©hese nerves are exposed after having left 

the brain. 

mges which^k^motor oculi, the abducens, and the patheticus 
;o in thei^Jrfi at the base of the brain are rarely essential. It 

The changes whic] 
may undergo in theiK 
is more commonly ex-t 

(ernal causes which influence them. 

is pressure exerted upon their trunks. This may be 
spontaneous or traumatic, which occur in the cranial 

S xfudations accompanying meningitis; to tumors which originate 
cerebral substance , or in its envelopes , or in the bony tissue of the 

cranium. At times these nerves participate in an inflammatory process 




developed in their vicinity ( meningitis , progressive general paralysisf and 
thrombosis of the cavernous sinuses ). Finally, they may be destroyed or 
compressed at some point of their course by traumatism [fracture of the 
cranium). 2 

Certain tumors of slow growth and of small volume may produce very 
localized paralyses of the motor nerves of the eyes. This is especially the 
case in aneurisms developed on the arteries which are in intimate rela¬ 
tions with these nerves. Thus, Rauchfuss 3 has observed a paralysis of 
the left motor oculi produced by an aneurism. of the left posterior cerebral 
artery, the size of a pea, which pressed upon this nerve. 

Nieden has reported an observation of an isolated paralysis of the right 
patheticus due to the pressure exerted upon the nerve by the pineal gland, 

which had undergone cystic degeneration. 

Syphilomata may produce the same result. 

Tumors of the cerebellar fossa, those of the pons Varolii, those of 
the petrous bone, and those which have their origin in the walls of the 
cavernous sinus, are those which most expose the motor nerves of the eye 
to pressure. The last two classes generally involve also paralysis of the 
other bulbar nerves. 

The motor nerves of the eyes are so liable to be damaged by traumatisms 
of the cranium, that paralysis of these nerves is sometimes the only symp¬ 
tom present when the injury has not been sufficiently severe to cause grave 
changes in the intra-cranial mass. Thus, fractures of the base are frequently 
accompanied by paralytic strabismus, especially those which concern the 
petrous bone. M. Panas has called attention to the fact that in such a case 
the paralysis of the external motor is more frequent than that of the third 
and fourth pairs. This is due, according to that author, Tq^we peculiar 
relations of these different nerves with that region of the erSmum. 4 

In contradistinction to paralysis of the common im^Joculi of bulbar 
origin, that which is produced by pressure or ruptutfSyff its trunk at the 
base of the brain is, if not always absolute, at leq(SYfrequently total,—that 
is to say, it extends to all the muscles innervating the affected nerve. 

Our fourth group comprises paralyseJ&jAte to lesions of the terminal 
orbital branches of the motor oculi nerves. vJ 

At their entrance into the orbit,vupbugli the sphenoidal fissure, the 
nerves which supply the muscles^q^SM eye are still very much exposed 

1 Magnan, Note sur la scleros/7Ic|Sferfs optiques et des nerfs moteurs de l’oeil dans la 
paralysie generate (G-azette Medic^Wte Paris, No. 44, 1877). 

2 For the different sympftnG^vhich may accompany the basal paralyses of the motor 
nerves of the eyes, and for/R^peculiar value of these paralyses as concerns the localiza¬ 
tion of a cerebral lesioa, selvtfnthnagel, Topische Diagnostik der Gehirnkrankh., 1879. 

3 Rauchfuss, ZqANj^ihstik der Hirnembolie, Petersb. Med. Wochenschr., No. 7, 1878. 

4 Panas, De la paSjuysie du nerf moteur oculaire externe consecutive aux traumatismes 
du crane, Archr^s^d'Ophtalmologie, i. p. 3,1880-81 ; and Genouville, Fracture de la base 
du crane a^ec p^ilysie du nerf moteur oculaire externe, Archives d’Ophtalmologie, Feb¬ 
ruary, 1883pv 



to the injurious influences which may result from lesions of the skeleton 

( 'periostitis , gumma , fractures). 

Even in the interior of this cavity, they appear to be subject to in¬ 
flammation of their neurilemma in a spontaneous way (perhaps a part of 

the motor paralyses of the eye afrigore is due to an inflammation of the 

muscular tissue itself), oftenest under the influence of cold {rheumatismal 

paralyses ), or consecutively to inflammation of the cellular tissue of the orbit. 

Thus, Landesberg 1 has observed a paralysis of almost all the muscles 
of both eyes, without any cerebral symptom, in consequence of exposure to 
cold. The cure was perfect at the end of a short time. 

Von Hippel 2 has seen a complete paralysis of the muscles of the eyes 

with symptoms of inflammation and oedema of the orbital tissue, which he 
attributes to a periostitis of the sphenoidal fissure. 

Perhaps it is to such changes that the paralysis sometimes observed in 
cases of dental caries (Baumeister has related a case of this sort) or of acute 
auricular rheumatism must be attributed. 

We have observed, with our clinical assistant, Dr. Gygax, a very strange 
case of paresis of the inferior rectus y caused by an inflammation of the mucous 
membrane of the antrum of Highmore. There was, at the same time, a cer¬ 
tain degree of protrusion of the globe; but the proof that it was not merely 
a question of displacement of the globe by pressure was to be found in the 
very distinct symptoms of paresis of the inferior rectus. Thus, there was 
strabismus sursum vergens of 10°, with slight divergence of the eye and 
corresponding vertical diplopia, increasing when the patient looked down¬ 
ward and to the affected side, diminishing when he looked in the opposite 


It is evident that a tumor at all vohiminousJn^emping itself in the 

narrow space which the orbital terminations^me motor nerves of the 
eye occupy, has for its effect their comprese&cr or annihilation. But in 
such a case the lesions of the nerves araSytfden in those of the muscles 

which they innervate. 

Paralysis of orbital origin may 

ftial and localized, but it is oftenest 

tter is g^MAly accompanied by chemosis, and there is a 
of ex almos, still more accentuated when caused by a 
lopfl^Jn this tissue.—Finally, the internal and external 

. certain 

found, in m^njpcases of this kind, a certain degree of anaesthesia of the 
skin of thgQ(>r ehead. 

lanHesberg, Ueber doppelseitige Augenmuskellaehmungen, Berliner klinische 
hchrift, SS. 645-648, 1874. 

on Hippel, Laehmung aller Muskeln eines Auges, Bericht Ophthalmologische 

.inik, Giessen, 1879-1881, S. 22. 



Fraenkel 1 describes a sort of serous degeneration of the ocular muscles 
in progressive amentia. This lesion, moreover, does not appear to have 
caused strabismus. 

Mention should also be made of the congenital paralyses of the ocular 
muscles. They are not so rare as seems to be generally supposed. Schar- 
pinger 2 relates a case of congenital paralysis of the sixth and seventh pairs 
(abducens and facial). 

We have ourselves observed several cases of congenital ptosis. 

It is possible that many cases of strabismus in young children, which 
are usually considered as non-paralytic, because the symptoms which charac¬ 
terize paralysis of the ocular muscles are not very pronounced, are properly 
referable to congenital paresis. If diplopia is lacking, it is simply because 
binocular vision did not exist at the time of the production of the paresis. 
The association of the movements of the two eyes likewise undergoes, in 
such a case, changes capable of interfering with the classic aggregation of 
the symptoms of muscular paralyses. 


All the etiological circumstances which we have just enumerated gener¬ 
ally present themselves at once to the mind of the physician, in the presence 
of a muscular paralysis of the eye. A careful anamnesis and examination 
will enable us to eliminate the majority of them, by directing our attention 
more especially to certain ones among them. Generally, affections of this 
kind, when they arise in young and apparently healthy individuals, when 
not due to traumatism, are of rheumatic or syphilitic origin. Hence one 
ought to suspect the presence of syphilis in such a case, andAnquire con¬ 
cerning the patient’s morbid antecedents.—If the affection ,n)subsequent 
to exposure to cold, and is accompanied by frontal a»aCf)eriorbital pain 
with painful sensations when the eyes are moved, it i^Qjkely to be of rlieu- 
matismal origin.—If neither of these two causes&fc^«irs to be in action, it 
is best to seek for symptoms of tabes dorsalfask kdi as cubital anaesthesia, 
cardialgia, the decrease of sensibility, shooting p»fns, difficulty in micturition 
and defecation, etc., the abolition of the tfsSSlar reflexes, and—a symptom 
much more characteristic—the immobvjkv of the pupil under the influence 
of light, its contraction accompanying convergence. (Argyll-Robertson.) 

The urine ought always to ta^^imned, in order to learn whether or not 
it contains sugar. 

If all these researches^e£iain without result, we may investigate the 
possibility of the paraj^gk being due to poisoning by lead , diseased meat , 
tobacco , alcohol , or other injurious substances which we have men¬ 
tioned above ; lysteria has to be taken into account. 

The naturo^^CTie paralyses which follow diphtheria will soon be recog- 

1 Frae^lpMbeutsches Archiv furklin. Med., v. 20, H. 5, 1877. 

2 Sekarpeger, New Yorker medicinische Monatsschrift, Ueber angeborene beider- 
seitigelfi^roplegie, December, 1889. 




nized, thanks to the anamnesis. The latter, however, ought to be pecu¬ 
liarly exact, considering all the details. It may happen that paralyses are 
produced in consequence of an angina which is without any apparent gravity 
and which may have escaped the patient’s notice. 

Those which may be dependent on a circulatory disturbance of the 
nervous centres are generally accompanied by the cerebral symptoms cus¬ 
tomary to such lesions,—cephalalgia, a feeling of heaviness of the head, 
buzzing in the ears, indisposition for work, somnolence, etc. One is to seek 
carefully the causes which may bring about these troubles (alterations of 
the digestive functions, constipation, overwork, over-indulgence at table or 
in alcoholic beverages, intestinal parasites, and febrile processes). 

If the paralysis be due to an anatomical alteration of the intra-cranial 
tissue , it cannot fail to be accompanied by other symptoms, such as hemi¬ 
plegia or hemiparesis, monoplegia, facial paralysis or paralysis of the other 
bulbar nerves, more or less complete abolition of the cerebral functions, 
vomiting or epileptiform seizures. 

Finally, hysteria will betray itself by its well-known signs,—plaques of 
anaesthesia or complete hemianaesthesia, ovarian pain, the bulbus hystericus, 
determining pressure-points, convulsive seizures, more or less marked uni¬ 
lateral amblyopia with diminution of the retinal functions, and narrowing 
of the visual field for white and for colors, as we pointed out in 1875. 1 

We found and demonstrated to our students, several years ago, a char¬ 
acteristic symptom by means of which to distinguish paralytic ptosis from 
an occlusion of the eye in consequence of a spasm of the orbicularis. In 
the case of paralysis, the patient seeks, as is well known, to substitute a 
contraction of the frontal muscle for the insufficiei^^ction of the levator 
palpebrae superioris. The skin of the forehead te3h£refore folded, and the 
eyebrow of the affected side is higher than the healthy side. On 

the contrary, when there is spasm of the^Kicularis, the eyebrow of the 
affected side is lower than that of the h^nlfiy side. 

At another time, in connection wtfEV double ptosis of hysterical nature, 
I noticed the following fact. I t^d xlfe patient to look at my eyes. She 
leaned her head backward in ord^r)fo be able to see under her lowered lids. 
I then gently inclined her h^ forward, at the same time enjoining her 
to continue to fix my eyeajOjn proportion as her head was lowered, her 
eyes and eyelids were Finally, when her chin almost touched her 

chest, it was foundationer upper lids were so much raised that they were 
almost hidden unVlepthe eyebrows. This was an irrefutable proof that it 
could not be^Jjuestion of paralysis of the levators; otherwise, at the 
slightest attOr^ to lower the head the pupils would have been hidden 
under tife^iert lids. 

the diagnosis of the seat of the lesion , it can be made accurately 

V* Landolt, De l’amblyopie hvsterique, Archives de physiologie normale et patho- 
gique, 1875, p. 624. 



only if all the peculiarities of ocular paralysis are carefully taken into con¬ 
sideration along with the other concomitant symptoms. We have already 
seen that the partial paralyses of the common motor oculi, especially those 
wherein the pupil and the accommodation perform their functions normally, 
very probably have a nuclear origin ; while changes in the nervous cords 
at the base of the brain and in the orbit almost necessarily entail a total 
paralysis of this nerve. 


The duration, evolution, mode of termination,—in short, the prognosis, 
—of a motor paralysis of the eye naturally all vary according to the 
cause which has provoked it. If it be due to a curable affection, the 
nerve will be able, little by little, to resume its functions if, at the same 
time, the interruption has not been too prolonged, and if its fibres or 
the ganglion-cells of its nuclear centre have not undergone too profound 

Thus it will be understood that paralysis due to a simple circulatory 
disturbance of the encephalon or of the isthmus of the encephalon may 
be easily curable, as soon as one shall succeed in suppressing the morbid 
influences which are in action. The same is true of hysteria , in which 
the nervous paralyses depend on functional lesions. 

Paralysis consequent upon hemorrhage in the cerebral substance is like¬ 
wise susceptible of cure when the effusion has only pressed upon the nerve- 
cord. It is equally so in cases where a small hemorrhage .(the rupture 
of an aneurism) has not produced a too extended destrqeti&mof the gan¬ 
glion-cells of the nuclei or when it has acted simply by^^mux and com¬ 
pression on its vicinity. In hemorrhage into the heraGpJieric substance, at 
the time when the secondary contractions of tlq >s take place,—con¬ 
tractions which announce the irreparable destarmen of the internal cap¬ 
sule,—the other phenomena of compression'siorate, the unilateral or 
ocular paralysis entirely disappears. ^ 

This is not the case, of course, whenQi abundant and sudden hemor¬ 
rhage has reduced to a pulp the nd^us substance of the protuberantial 
nuclei, when they have been invpljk^in a focus of softening of the brain, 
of acute or chronic (sclerosis) %™£pnalitis, or when any other tumor than a 
syphiloma compresses or abo^ics them. 

It is, as a rule, wron^fco make a favorable prognosis concerning the 
tabetic paralyses of ftj^Jhotor nerves of the eyes; although, as we have 
said, these paralys^^cadily disappear of themselves or under the influ¬ 
ence of treatn^^tney may return and become permanent. It ought not 
to be forgottaQvhioreover, that they may persist from the outset in many 
cas< s, and^at they have a pronounced tendency to invade all the muscles 
°f thaey^ like those that accompany progressive bulbar paralysis. How- 
evei^ >©nedikt tells of having seen such paralyses cured by very prolonged 



electrization. The same remarks are applicable to paralyses depending 
upon sclerosis plaques. 

Pressure upon the nervous trunks at the base of the cranium or in the 
orbit by meningitic exudations, by thrombosis of the cavernous sinus, by 
a tumor, or by a bony particle, necessarily entails an unfavorable prognosis. 
The prognosis is doubtful when the nerve lesion is of traumatic origin. It 
may happen in such a case that it is a question simply of compression of 
the nerve by a hemorrhagic effusion, whose resorption brings about the 
restoration of the conductibility; but too often the nervous trunk is par¬ 
tially or wholly destroyed by the injurious cause, or is included by a frac¬ 
ture callus, and irremediably lost. 

The prognosis of paralysis due to syphilis is not so serious, because of 
the amenability of these lesions to treatment. Although disturbances of 
motility of specific origin usually improve under proper treatment, yet it 
is well not to abandon one’s self to too great delusions as concerns the 
result of such treatment. External ophthalmoplegia, among others, or 
bulbar paralysis of syphilitic nature does not always improve under the 
influence of such medication. 

The same remarks are applicable in the case of lead poisoning. Dia¬ 
betic paralyses and those of diphtheritic origin are generally benign, and 
get well with the lapse of time, inasmuch as the ocular disturbances are 
not complicated by lesions of other nerves essential to life, such as those of 
respiration and circulation. 

So-called rheumatic paralyses may get well entirely and rapidly. They 
persist, on the contrary, with great obstinacy, or become incurable, when 
they are long neglected, or when the inflammatorv^^ons 0 f the nerves 
have been peculiarly profound. (x* 

The same is true of the paralyses which aja&Hnpany migraine. Paral¬ 
yses associated with migraine—that is to ^J^hose which manifest them¬ 
selves in persons subject to this mala^^generally disappear promptly 
at the end of a few weeks. But tl^^Sinost always return, sometimes 
affecting another muscle, sometimc^even the other eye, or attacking both 
eyes simultaneously. Hence if tbQmmediate prognosis is not unfavorable, 
the ultimate prognosis is far X0 1 being altogether good, and so much the 
more since migraine may b^0^ prodrome of a serious cerebral affection. 

The hysterical para^^jgs'fand contractions) of the ocular muscles com¬ 
port themselves lib «e (J) 1 other morbid manifestations to which hysteria 
gives rise. They may persist during entire years with an obstinacy defying 
all imaginable, tSjy apcutic efforts; at other times they disappear as if by 
magic. far as our experience goes, they are rather resistant to, 

than sus^aytiule of, improvement. 

Tlf SS lar muscles being in great part inaccessible to the direct appli¬ 
cation of electricity, we are deprived of this precious means of diagnosis 
^aKpbr the information which it might furnish us with reference to the 
(Q^-ognosis. However, a careful consideration of all the facts which we 



Lave discussed—the anamnesis of the patient, the examination of the func¬ 
tions of his cerebro-spinal system, and the general phenomena which may be 
presented— permits of our detecting, with relative certainty, the seat of the 
paralysis, its nature, and the consequent prognosis. 

When a muscular paralysis of the eye is curable, it is seen to amend 
more or less rapidly, whether in a spontaneous way or as the effect of 
appropriate treatment. The distance between the double images dimin¬ 
ishes by degrees, the domain of single vision broadens at the expense of 
that of the diplopia, and the deviation of the eye becomes less striking. 
The head assumes a more natural position, the excursions to the side of the 
paralyzed muscle gain in extent and ease, and the field of fixation increases 
in this direction. Jt may thus happen that at the end of a few weeks the 
cure becomes complete. There persists, at most, a slight diplopia in the 
extreme direction of the eyes to the side of the paralyzed muscle, the last 
vestige of which is at length effaced. 

But it may also happen that, after having made a certain amount of 
progress, the amelioration remains stationary, and perfect recovery is ob¬ 
tained only by an extremely long and persevering treatment. 

Finally, there are many cases in which the paralytic deviation becomes 
permanent. The visual troubles which accompany it amend, however, little 
by little. The diplopia, with the vertigo that it produces, becomes less 
troublesome; the competition between the two visual fields is overcome by 
virtue of the exclusion of one of them. The fixing eye (sometimes the one 
which is paralyzed) remains the sole master of vision. As to the other, it 
becomes accustomed to its new position of equilibrium, and succeeds finally 
in accurately projecting its retinal images. The muscle or.umscles which 
keep the eye in its vicious position, being permanently sm^Jcned, undergo 
nutritive modifications tending to diminish their real krfhgrn in the absence 
of normal contraction. They become the seat of called secondary 
contracture. (Von Graefe.) 

Secondary contracture develops rather and it is necessary to 

combat it, even in cases which are certaii^tirTecover. According to what 
we have just said, it is developed as in the sound eye, when the 
affected eye is used for fixation, as ii^ie affected eye, when this deviates, 
which is usually the case. It maj^ersist after a complete return of the 
conductibility of the nerve, a^ Ive rise then to a sort of concomitant 
strabismus, accompanied b^ @nptoms similar to those of the paralytic 
strabismus which gave risSsto^it. Their distinction sometimes presents dif¬ 
ficulties, which the exn^fjnation of the fields of fixation of the secondary 
deviation and of the^5yojection may not always overcome. 

The seconda^vGinges in the muscles, following paralysis of the nerves 
which supplyN^Jhn, are as yet very little known. It seems, according to 
Von Graefi^hat the paralysis of an ocular muscle does not certainly entail 

Mauthner, Nuclear»laehmuiig, S. 308. 



tions to fulfil: first, to dissipate the visual disturbance which troubles 
the patient, until he is completely cured; second, to promote this cure, at 
the same time preventing the formation of secondary contractures of the 
antagonists of the paralyzed muscles. 

In certain cases a surgical operation may be required to restore single 
binocular vision, or at least to remedy the disfigurement of the strabismus, 
in the principal direction of the gaze. 

The first object may be achieved in different ways. The simplest means, 
when the deviation is considerable and the diplopia very marked, consists 
in covering one of the eyes with an opaque screen or with a ground glass. 
It will naturally be the affected eye which is subjected to this occlusion, 
whenever choice is possible. The secondary deviation being, indeed, more 
considerable than the primary, it would be very inconvenient to abandon 
the sound eye to this deviation, which might occasion a secondary contrac¬ 
ture of the muscle or of the group of muscles which produces it. How¬ 
ever, we may be forced to do this, when the visual acuity of the sound eye 
is much inferior to that of the diseased one. The choice of the fixing eve 
is almost always instinctively made by the patient, especially when both 
eyes are the seat of a motor paralysis. 

When the deviation is slight, and the double imagtfs^are consequently 
very near each other, the paresis may be remedied wiffl^he aid of prismatic 

We have, in the section on strabometry, JijGW acquainted with the 
action of these diopters. 2 

By changing the direction of lumi iymsQys, they may cause the image 
of the object fixed by the healthy eye t^fifll upon the fovea centralis of the 
deviating eye, and thus bring abc*rtSfusion of the two images,—that is, 
binocular vision. _ ^ 

Now, the prismatic deviatkW^hdng place towards the base of the prism, 
the apex of the prism ka^J-point to the side towards which the eye 
deviates. In convergoatf^trabismus, the apex of the prism is towards the 
nose, in strabismus sursum vergens, the apex is upward, etc. 

It is necessary, moreover, that the optic effect of the prism be equal 
to the deviationvOhe eye. A strabismus of 10° requires a prism of 10° 
of deviathn^^J^trabismus of 20°, a pri sm of 20°, etc. (See page 49.) 3 

1 Jahresbericht ueber die Leistungen und Fortschrute im Gebiete der Oph- 

thalm<^)gie, Tubingen, 1884, SS. 343, 605 

^V%°rding to Monoyer, transparent substances cut so as to produce a dioptric effect 
gireSsnled “ diopters.’’ 

3 We call a prism which produces a deviation of 23° a prism of 20°, etc. 



Here we notice at once one of the weak points in the use of prisms in 
paralytic strabismus. We know, indeed, that the deviation increases to the 
side of the affected muscle, while it diminishes in the opposite direction. 
Hence the same prism can neutralize the diplopia produced by the strabis¬ 
mus in but one direction. This is the case, indeed, in complete paralysis. 
But in this case prisms are not of much use, for a cogent reason, with 
which we shall presently become acquainted. 

In muscular paresis of slight degree, on the contrary, prisms render 
great service. When the deviation is a horizontal one, the patient readily 
remedies the insufficiency, or the excess of action, of a prism, by an in¬ 
crease or a diminution of his convergence, or by a slight rotation of his 

This rotation will be specially useful to him in the case of vertical 
deviations. Let us suppose, for instance, an eye directed upward by three 
degrees, in consequence of the paresis of a depressor. A prism of 3°, with 
apex upward, will bring the images to the same level when the gaze is 
straight ahead. If the patient lowers his eyes to look downward, the 
diplopia will reappear, because the affected eye cannot follow the healthy 
one, on account of the insufficient action of the paretic muscle. But the 
patient will soon learn to lower the head in order to escape this embarrass¬ 
ment. He will raise it, on the contrary, if, elevating his gaze, the prism 
should prove to be too strong, because the strabismus diminishes in this 

We have, moreover, pointed out, when discussing strabometry, the fact 
that when two images are near enough to each other—in other words, when 
the retinal image of the deviated eye is formed near enough ±o the fovea 
centralis—fusion is often spontaneously accomplished, so^H^t a prism 
whose action is somewhat less than the degree of theOxteibismus may, 
notwithstanding, suffice to correct it. 

Of course, a prism could not remedy the imffiption of the image 
belonging to an eye which has undergone a i^fiMttgical rotation around 
its antero-posterior axis. But here again ol^e^5tion proves that, when 
the images are formed in each eye on thK^fovea centralis, or very near 
it, the obliquity of one of them is easilWeutralized, whether by an in¬ 
clination of the head or by the couaflwifed action of the muscles of both 

But the use of prisms, so v^Wmne for the correction of strabismus, is, 
unfortunately, limited by certain other optical effects which are peculiar to 
them (coloration of outlin^s/tmanges in the form and relief of objects), and 
also because of the waiN^r of such glasses, as soon as they exceed a few 
degrees. Thus it; hfN^hnt a prism producing more than three degrees of 
deviation is woj^S^Kh difficulty. 

It is true t^aKboth eyes may be furnished with prisms, so that, instead 
of placino^vjfysm of 6°, with its apex nasal, before the left eye, this eye 
being afeM with convergent strabismus, a prism of 3° may be placed 



before each eye. Each of the prisms ought, necessarily, to have its apex 
directed towards the nose. 

The same is true in the case of divergent strabismus. Two prisms 
whose apices are directed towards the temples, when placed before the two 
eyes, have the same effect as a single prism whose strength is equal to the 
sum of that of the other two, this one being placed before one eye.—The 
same thing occurs again for vertical deviations. Instead of placing the 
prism of 7°, with its apex upward, before a left eye which deviates upward, 
we may give three degrees to this eye and four degrees to the other; only, 
for this latter, the apex of the prism will be directed downward. 

This distribution of the correction of the two eyes is particularly indi¬ 
cated in intermediate deviations. In such a case, the prism which corrects 
the horizontal diplopia may be placed in front of one eye, and that which 
corrects the difference in height, before the other. 

It is self-evident that for persons who usually wear spheric or cylindric 
or combined lenses, we should utilize the two surfaces of the prism to cor¬ 
rect the optical defect; in other words, the prism will be combined with the 
correcting glass of the ametropia. 

The symptomatic treatment having been instituted, we must direct our 
attention to the restoration of the conductibility of the nerves, and of the 
contractility of the muscle. The means we employ must naturally vary 
with the cause of the paralysis. Rest, derivative medication, a regimen 
appropriate to the individual sanitary conditions, will happily modify 
those cerebral changes dependent upon anaemia, hyperaemia, plethora, etc. 

In syphilis , specific remedies should be employ^!,— e.g ., a course of 
mercurial inunction or injection and iodide of pohi^Nkn. 

A suitable diet, along with the administratjwvbi Carlsbad or Vichy 
waters and of bromide of potassium, formsjfoe proper treatment of dia¬ 
betes . vC/ 

Lead poisoning requires sulphur h^tflwand iodide of potassium inter¬ 
nally ; hysteria , hydrotherapy, electi^i^^intispasmodics, and moral suasion. 

If the paralysis be due to (peripheral affection of the motor nerves 
caused by cold, it may be well © oppose it with the customary antiphlo- 
gistics: local bleeding, dianlj^esis by means of warm beverages or pilocar¬ 
pine, moist packing, \a$d&ps, and, if rheumatism assume an acute and 
general form, salicyl^ sodium. Later, the application of a vesicatory 
has been recomn^i(j()r as favoring the complete resolution of the inflam¬ 
mation of the oekkAnotor nerves. 

Whateve^CfJay be the causal indication to be fulfilled, electricity is 
consideredJ0uimportant adjuvant. Stimulation of the nerve is ascribed 
to it, illation of its nutrition and of its special function, the excita- 

tionSNfche contractility of the muscle, which prevents degeneration of its 


The constant current and faradization are both employed under such 
^circumstances. The mode of application varies much according to different 



authors. Some advise acting directly on the great sympathetic by placing 
the negative pole on the superior cervical ganglion, the positive on some 
point of the orbital border close to the paretic muscle. 1 Others recom¬ 
mend the electrization of the affected nerve itself; they apply the cathode 
to the back of the neck, the anode around the orbit. The current ought 
generally to be weak (from four to six elements) and of a duration of from 
two to five minutes ; sittings may be repeated on alternate days. 

If it be desirable to use the induced current, it may be applied directly 
to the muscle. For this purpose, the electrode, in the form of a little 
flattened knob, isolated on one side, is introduced under the lids as far back 
as possible, and its free surface applied on the diseased muscle. Cocaine 
anaesthesia will facilitate this little manoeuvre. 

At regular intervals, the effect of the treatment is to be ascertained by 
the aid of careful strabometry. If our efforts are crowned with success, 
there will come a time when the deviation can be corrected by a prism weak 
enough to be permanently worn. This will hasten the cure by stimulating 
binocular fusion. 

J. Michel proposed, in 1877, a treatment of muscular paralysis which 
may be called mechanical This method consists in seizing the conjunctiva 
over the insertion of the paralyzed muscle by means of fixation forceps, 
and turning the globe forcibly as far as possible in the direction of the 
action of the muscle, to and fro, for a few minutes. Charles Stedman 
Bull 2 treated in this way, prior to 1887, twenty-one cases, of which eight 
were cured, six were improved, and seven remained stationary. Patients 
submit unwillingly to this method of treatment, which is undoubtedly 
painful. . 

We have already twice mentioned the tendency that most^™its mani¬ 
fest to fuse the double images as soon as these are brought (gp enough to¬ 
gether. This is the reason why the degree of strabismi determined by 
the correcting prism is generally less than that results from the 

diplopia. The treatment of strabismus whicly.j^^'Be called orthoptic is 
founded upon this observation. By some mrai^^lrether with the help of 
a prism or simply by means of rotation ofJ|i£ head, the two images are 
brought so near together that they may ba fused. Then an attempt is made 
to maintain the fusion under less fa\^|*8le circumstances. This is done 

either by diminishing the strengtfgjof? the prism 3 * 5 or by turning tho 
I patient’s head slowly in the dirpfidn opposite to the strabismus, while he 
j still tries to maintain the fusi^^pTn this way, the contraction of the paretic 
I muscle is stimulated. It j^true that in complete paralysis this device is 
unlikely to be successfu^y* 

I 1 See, with rofei^^^this, Benedikt, Erb, Neumann (in Landolt, art. Strabisme, 
Dictionnaire encyelopk^ue des sciences medicates, p. 723, 1883). 

2 Transactions^ the American Ophthalmological Society, 1887, p. 459. 

3 The dout^^yrRm is of great use in such a case, because the diminution is made 

gradually aijWithout the patient’s cognizance. 




One may also, with a view to varying the exercises, use for the same 
purpose our stereoscope . (Fig. 41.) 

When this stereoscope is used, the eyes are adapted, by means of proper 
glasses (six or seven dioptries for emmetropic eyes) to the images at the 
bottom of the instrument, and to the two images is given a separation in 
accordance with the divergence, convergence, or the difference in height of 
the lines of sight in the position of rest. For the usual length of the base 
line (sixty-four millimetres) this distance ought to exceed this value by 
about ten millimetres for seven degrees of divergence, and to be less by an 
equal amount for a like degree of convergence. Thus, if we have to do 
with a convergent paralytic strabismus of fourteen degrees, we should give 
to the two images a separation of about forty-four millimetres. If we are 
concerned with a divergent strabismus of ten degrees, the stereoscopic images 
are to be separated by about seventy-eight millimetres, etc. Under such 
circumstances, the stereoscopic fusion of the two images will be obtained. 
This result having once been achieved, we seek to get gradually the normal 
separation—that is to say, parallelism—of the lines of sight. One may 
even attempt to surpass this end, when one has succeeded in bringing about 
parallelism of the divergent lines of sight, and exercise them little by 
little in fusion in the convergent position. 


When the paralysis of an ocular muscle is not susceptible of medical 
cure, one is justified in having recourse to surgical means for remedying 
the annoyance which it causes the patient. 

Personally, we have operated for the correction (>^\awdytic strabismus 
oftener than is generally done. We have attackec s which many would 
have considered as noli me tangere for surgemGpa we have never found 
cause to regret our hardihood in this resped*^\*lt is true that our method 
of operating differs somewhat, as will from that generally in use. 

Not being able to restore the conti^oi^ity of a paralyzed muscle, oper¬ 
ators have sought to weaken to an^Npial degree the associated muscle of 
the healthy eye, for instance, the^internal rectus of the right eye in a case 
of paralysis of the external lW&g of the left eye. 

Some have even gone^^Owis to recommend the tenotomy of all the 
muscles acting in the^ft^izontal meridian on the healthy as well as on 
the diseased eye, t^S* pwpose of this general tenotomy being to remedy 
the paresis of a sjpgt^ne of the muscles in question. 

Thus, in aJ&>£)of paresis of the left external rectus, the right internal 
rectus would^e/tenotomized; and, under the pretext of “ equalizing the ac- 
commod^jW^ in the two eyes, one would add to this tenotomy that of the 
left inte^ku rectus, as if the accommodation of an eye depended on the 
slrpfeflh of its internal rectus muscle. 1 Finally the externus of the healthy 

* See A. Graefe, in Graefe und Saemiseh, Handbuch der gesammten Augenheilkunde, 



eye would be tenotomized, in order to restore the muscular equilibrium of 
this eye! 

In my opinion, we ought to proceed quite otherwise. Given the 
inertia of the paretic muscle and, consequently, the difficulty of obtaining 
a field of binocular fixation of considerable extent, it is necessary, at least, 
that the field of fusion which we create shall be in the most useful direction 
for the individual,—that is to say, in the median plane for the muscles 
that act horizontally, in a plane slightly lowered for those that act ver¬ 
tically. This is true not only when binocular vision exists, but also when 
the operation is done solely with the cosmetic purpose of remedying the dis¬ 
figurement caused by the deviation of the eye. 

Moreover, I always abstain from weakening one of the muscles of the 
healthy eye. It is precisely in those cases for which the tenotomy on the 
sound eye has been most recommended that I practise this least; in cases 
of simple paresis. 

There is always a chance of recovery from a paresis. On the con¬ 
trary, the defect in motility resulting from the setting back of a muscle, 
far from recovering, is always on the increase. One thus incurs the risk 
of creating for the healthy eye a strabismus worse than that of the paretic 
eye. For this reason, we prefer to treat paralytic strabismus (as well as 
the non-paralytic strabismus) by muscular advancement rather than by 

Let us take an extreme case, a total paralysis of the external rectus of 
the left eye. The patient sees single only in the extreme right part of his 
field of fixation. Diplopia, as well as the disfigurement whicJjVesults from 
his convergent strabismus, annoys him ; he wishes to be reX&ed of it. 

In this case, I should perform an energetic advances^lt with resection 
of the external rectus on the diseased eye and a simpli^S^'ancement of the 
same muscle on the other eye. If necessary, thexlptomy of the internal 
rectus of the diseased eye could be added. 

Binocular vision and, with all the mopQtSn, the desired cosmetic 
effect are thus obtained, not only for the JS*rimary position,” but also for 
raising and lowering the gaze. v-A 

t ^ ^ ey ldent that, as soon as the afc^fefeon of the patient is directed to an 
object situated at the left, the qogra^nt strabismus and the homonymous 
diplopia will reappear, becausa^he inertia of the paralyzed muscle. On 
the right side, on the con/mWthere will be crossed diplopia, because the 
left eye only imperfectlwfoffows the movement of its fellow in this direc¬ 
tion. It lags behmdSj^iuse of the operative weakening of its internal 
rectus.. There is dhA^ent strabismus to the right, convergent to the left. 

. Tllls 18 in OT* e m a case of tot al paralysis, but certainly less annoy¬ 
ing than the coition produced by tenotomy of the internal rectus of the 
healthy SgApe who watches carefully the effect of his operations knows 
very in order that a tenotomy may counterbalance a muscular 

parakA^ an extreme setting back is required, such a setting back as is 



obtained only by means of sutures applied over the antagonist,—the thread- 
operation, as von Graefe called it. Thus the eye is drawn out of its mus¬ 
cular funnel, and its mobility greatly damaged. This is a method which 
we absolutely condemn, for reasons to be given in the next section. 1 

Moreover, the patient soon learns to remedy, by the rotation of his head, 
the insufficiency of the movements of his left eye. 

As to convergence, it certainly will be diminished by the tenotomy of 
the left internal rectus, but not nearly so much as by the thread-operations 
on the other eye. When the paralysis is not complete, no tenotomy is 
necessary to restore binocular vision. We may refer, for instance, to the 
cas'e of a carpenter who could not do his work on account of a paresis of 
the rectus externus of his left eye. The paresis, indeed, had caused a con¬ 
vergent strabismus with homonymous diplopia of 12°. We performed 
advancement of the external rectus of each eye , without tenotomy of the an¬ 
tagonist, but resecting several millimetres of the paretic muscle. The 
result was perfect fusion. The patient could even overcome an abducting 
prism of one metre-angle (r =—1); and as for the convergence, it exceeded 
the normal, in spite of the advancement of the abductors. 

In another case iu which the paresis of the external rectus had brought 
on a strabismus of only 5° 30', advancement of this muscle alone succeeded 
in establishing absolutely harmonious binocular movements. Convergence, 
divergence, and even lateral excursion became perfectly normal. 2 

Our operative method is, mutatis mutandis , the same for paralysis of 
the internal rectus . Only, divergent strabismus always shows itself more 
resistant to treatment than convergent strabismus. the strongest 

advancement of the internal recti on both eyes suf&j^ehly to restore the 
parallelism of the eyes, but does not give the pa^iQlNra converging power 
sufficient for his usual work. We may thenQSiture to tenotomize the 
external rectus of the diseased eye. But thiJSJias always to be done with 
great precaution, otherwise one runs ttfTy&k of changing the divergent 
strabismus into a convergent one, or ^emTJi creating homonymous diplopia 
for distance without doing away wit^jne crossed diplopia for near at hand 

When the paralysis of an(^ductor or adductor muscle is incomplete, 
when there exists only jfak&s *“with diplopia of but a few degrees, the 
surgeon’s task is a mucl^witer and much more thankful one. 

In such a case, i^often suffices, as we have just shown, to give to the 
enfeebled muscle ,(jpx its advancement, a more favorable insertion in order 
to restore binoenKr vision over a very large, if not to the normal, extent. 

The ant^^mst of the paretic muscle ought never to be tenotomized 

1 See 


To, Landolt, compte rendu of his clinique, 1878, Rapport sur le Strabisme, 
SevetfbfcXlnternational Congress of Ophthalmology, Heidelberg, 1888; Archives d’oph- 
JthlN^logie, 1880, i. p. 594; International Medical Congress, Washington, 1887. 

^Landolt, Traitement chirurgique du Strabisme, Archives d’ophthalmologie, 189G, 



solely, as has been advised. 1 If the insufficiency of the tenotomized muscle 
equal that of an even moderately paretic muscle, it becomes a considerable 
source of annoyance, even in the lateral excursion, but especially in con¬ 
vergence, when the setting back has been performed on an internal rectus. 

The tenotomy ought only to aid the advancement of the paretic muscle, 
and ought always to be executed very moderately, for advancement increases 
the excursions of the eye , whereas tenotomy reduces them. 

Let us now consider the operative treatment of paralysis of the muscles 
which act vertically,—the depressors and levators of the eyeball. 

It might be supposed that our task would present in this case insuper¬ 
able difficulties. This would be true if we had to remedy all defects of 
direction and rotation to which paralysis of one of these muscles gives rise. 
Indeed, the obliques, as well as the superior and inferior recti, turn the eye, 
as it were, around three axes,—transverse, vertical, and antero-posterior. 
Now, even combined operations could not make good the troubles produced 
in these three directions. But, fortunately, experience has proved that the 
problem is not so complicated, and that we have in nature a powerful and 
benevolent aid, ready to fill up the gaps left by our always imperfect art, 
provided these lacunse be not too great. 

Let us again take a few examples and apply to them our principle of 
correcting strabismus for the most usef ul direction of vision. 

Suppose a paralysis of the superior oblique of the left eye. There is a 
strabismus sursum vergens, slightly convergent, and, moreover, temporal 
rotation of the eye around the antero-posterior axis. 

It has been advised 2 that this state of things be re by setting 

back the inferior rectus of the healthy eye, with a view J^reating in this 
eye the same strabismus as exists in the affected eye. <PKne right eye would 
thus be directed upward, to the right, and incline$t^5t r ards the left, like its 
paralyzed neighbor. (See page 25, Paralysis^^^e Inferior Rectus.) 

If by this means the retinal images of ^ot^ eyes be made parallel and 
brought to the same level, it is done at tjre^xpense of the lowering of the 
gaze. Now, the lowering is precisely the xjJiost useful direction of the gaze,” 
that for which, following our rule, A strabismus ought to be corrected. 
Von Graefe’s method adds to padxiAgical elevation of the affected eye the 
operative elevation of the heaft&^y e > making the lowering of this latter eye 
as difficult as that of the j*u^t)b eye. Indeed, the patient is then obliged to 
lower his head in order ft^jmxke good the insufficiency of his depressors. 

At any rate, we^sSSyld have recourse to this method only in cases of 
very slight paresis^yl^the superior oblique. 

If, on the^tfGKiry, the paresis be pronounced, we prefer to operate on 
*only. In fact, we find ourselves here in more favorable 

the affecte< 

’e, loc. cit., p. 82. 
r aefe, 18G4, Klinische 

Monatsblatter fur Augenheilkunde; Alf. Graefe, 
Hai/ftWcli der gesanimten Augenheilkunde, vi. 4, S. 81; Mauthner, loc. cit., S. 646; 
^^/Vrchiv fur Ophthalmologie, xxiv., 1878, S. 117. 

V v 




conditions than in paralysis of one of the lateral recti. In this latter case 
there is no resource, no power acting in the direction of the muscle which 
is put out of condition for work. When there is a paralysis of one of the 
depressors or levators, on the contrary, there still remains a muscle which 
acts in the same direction. Thus, in our example of paralysis of the 
superior oblique, we still have the inferior rectus, whose power we can re¬ 
inforce by advancement. 

If that did not suffice, we could increase the effect of our operation by 
the tenotomy of one of the levators of the same eye,—the superior rectus 
or the inferior oblique. The first of these two operations is very simple. 
The setting back of the inferior oblique would be impracticable, if we had 
to detach the tendinous insertion of this muscle from the posterior and 
external surface of the globe. But one can attack the inferior oblique at 
its origin near the margin of the superior maxillary bone, external to the 
orifice of the nasal duct. We described the method of this operation in 
detail some ten years ago. 1 

Theorists object that, since the inferior rectus, besides lowering the eye, 
turns it inward and gives it a rotation analogous to that produced by 
paralysis of the superior oblique, the convergent strabismus as well as the 
temporal inclination of the eye ought to be accentuated by the advance¬ 
ment of the inferior rectus. Our own experience as well as that of our 
former assistant, Dr. Eperon, has shown that such is not the case. The 
obliquity of the image as well as the homonymous diplopia disappears as 
soon as the difference in height has been corrected, whether this be by 
means of prisms or with the help of an operation. ^^\ eover > we have 
called attention to the fact that these two qualitieOyKliplopia are often 
lacking in paresis of the superior oblique, or/*Qhmfest themselves only 
when the gaze is sidewise. . 

Observation teaches us daily that the e}^s^kave a considerable power of 
harmonizing their movements after oj/raylvis performed on their motor 
apparatus, when binocular vision e^ts^If it does not exist, the slight 
degree of lateral deviation which <ajF> mpanies the paralysis of a levator 
muscle could not constitute a (^^gurement, and the rotation around the 
antero-posterior axis still less ^oW 

Let us now consider^til^kfmer rare case of the isolated paralysis of 
the inferior oblique . Tft^eye is directed downward and inward and its 
vertical meridian isQnluned towards the right. The first thing to do in 
such a case is to advance strongly the superior rectus muscle of the affected 
eye. If, at tluaA^ti of several weeks, there still exists a troublesome vertical 
diplopia, £\^ft^*when the patient looks downward, a very slight tenotomy 
of the^^^Sbr rectus of the healthy eye might be considered. 

OneN^mld in this way fulfil at the same time my principle of re-estab- 
1 binocular vision in the most useful direction (slightly downward), 

Landolt, La tenotomie de l’oblique inferieur, Archives d’ophthalmologie, 1885, p. 402. 



and that of von Graefe, which gives the healthy eye the same direction as 
the affected one. Indeed, by the artificial weakening of its superior rectus 
the right eye is directed downward and to the right, and its vertical 
meridian is inclined towards the right. Hence it turns round three axes 
in the same manner as the left eye, whose inferior oblique is paralyzed. 

The isolated paralyses of the superior and inferior recti are likewise 
very rare. They are occasionally seen, however. Moreover, these muscles 
may be involved in a pathological process in their immediate vicinity, or 
by a traumatism which enfeebles them. The surgical treatment, if it be 
necessary to have recourse to such, will be the same in any of these cases. 

It is true that we no longer find ourselves here in as favorable circum¬ 
stances as in the case of a paralysis of an oblique muscle. The muscle 
which combines its action with that of an oblique is one of the recti, 
whose advancement is easy. The muscles which are associated with the 
superior and inferior recti,—the inferior and the superior oblique,—on the 
contrary, can hardly be advanced. 

Hence, in the case of paralysis of a superior or an inferior rectus, we 
shall have recourse to the advancement of the paralyzed muscle itself. 
This advancement ought to be very thorough, and may be rendered still 
more efficacious by the resection of the muscle. 

If there be paralysis of an inferior rectus , it may be necessary to add 
to the advancement the tenotomy of the superior rectus of the same eye, 
for strabismus sursum vergens always implies great annoyance to the 
patient. I should not fear even to have recourse to the detachment of 
the inferior oblique of that eye rather than to the settb^Haack of the 
inferior rectus of the sound eye. 

It might be otherwise in a case of paralysis of tlv&*penor rectus. If 
the left eye be the affected one, this eye is directed ^jWnward and slightly 
outward, and its vertical meridian is somewhat hrSteed towards the temple. 

If, in spite of the advancement, with re^cftyfi, of the paralyzed muscle, 
there still persist a slight lowering of thC lefxeye, it would be permissible 
to produce an analogous lowering of thQjehlthy eye, because this direction 
is one of the most useful directions ight. 

This lowering of the healthy might be obtained by the tenotomy 
of its superior rectus, by tha^Xafifc Inferior oblique, or by the advancement 
of its inferior rectus. If tkSywference in height between the two eyes is 
but slight, I should n^jjtyect to the first operation (tenotomy of the 
superior rectus of tjn^gpund eye). If, however, the strabismus left is of 


several degrees, I^sfofffld give the preference to the advancement of the 
inferior rectum / v 

If all ^^nuscles innervated by the common motor oculi are affected 
with pareeis^there exist, at once, crossed diplopia and difference in height 
of th^*&l\ images: divergent and sursum vergens strabismus when the 
patkntiooks downward, deorsum vergens when he looks upward. 

^NWlien the horizontal deviation is very considerable relatively to the 



vertical deviation, it often suffices to correct the former in order to see the 
latter disappear. It is best, in all cases, not to cumulate surgical inter- 
ventions with the purpose of correcting simultaneously the lateral and 
vertical deviations. It is preferable to await the result of the horizontal 
strabotomy before proceeding to an operation in the vertical plane. 

The same rule is to be followed when the difference in height is the 
predominant defect. This defect is then to be corrected according to the 
principles above explained, and the muscles which act horizontally are to be 
attacked only when the first operation has not sufficed to remedy the diver¬ 
gent strabismus. 

But when the strabismus is considerable, and plainly intermediate, one 
may attempt the correction in both directions at once. 

The necessary operations may be performed on the same eye, or the 
lateral strabismus may be corrected on one eye and the vertical strabismus 
on the other eye. 

It also happens occasionally that both eyes are affected by muscular 
paralysis. We cannot enter into the details of all the different kinds of 
strabismus and motor troubles which may result from this. The principles 
which have just been set forth will suffice for the determination of the best 
method of operation in each case. 

Without opening the record of my operations, I shall cite two especially 
complicated cases of this kind. 

The first concerns a woman, forty years old, presenting indubitable 
symptoms of locomotor ataxia. She was subject to divc^bgrit and deorsum 
vergens strabismus, producing a vertical diplopia of ifafyi degrees, and a 
crossed diplopia of thirty degrees. Jo 

I knew very well that the tabetic paraly^a^iften disappear spon¬ 
taneously, but the patient had waited in vai^^Tyears for this fortunate 
occurrence. The diplopia annoyed her mnj0^ably, and she entreated me 
to rid her of it by any means. > 

There was no possibility of obtaiik^g this correction by means of pris¬ 
matic glasses. Hence I decided i^n operation, and performed, at the 
same sitting, the advancement internal rectus, with the tenotomy of 

the external rectus on the ri 
rectus, with the tenotomj^f 

ri^UVe, an< 
^4ne superi 

and the advancement of the inferior 
superior rectus on the left eye. 


During the operational told my students that it was not probable 
that these operatioii yvl inkl exactly correct the complicated and consider¬ 
able strabismus»d^ur patient; that, at best, we should expect to have a 
slight under- er-correction in one or the other direction ; but that we 
should e.'ij^Ocable to remedy this by means of a further operation, if it 
should necessary. 

khvncM was very happily surprised when the patient, only a few days 
lat<j0d|clared that she no longer saw double when looking straight ahead, 
X^ien looking downward. Binocular vision was restored, indeed, so 
O^Jerfectly, and without further operation, that tire patient, whom I have 



followed for years, could go about, attend to affairs, and do manual labor 
without the least inconvenience. 

A much more complicated and more difficult case, especially from the 
operative point of view, was the following. Princess T. had undergone an 
operation, by von Graefe, in her infancy, to correct a convergent strabis¬ 
mus. When she came to consult me, her right eye presented a divergent 
strabismus of fifteen degrees and strabismus deorsum vergens of thirty degrees. 

It was twenty-five years since the operation had been performed, and 
the patient could not tell me what had been done. She merely recalled that 
her eyes had been operated on several times. 

Even by a simple inspection, one could see that the internal recti of 
both eyes had been excessively set back. The caruncles were hidden under 
the internal angle of the lids, the sclerotic was bare to a great extent, 
and the nasal excursion of each eye was considerably limited, that of the 
left more than that of the right. The divergent strabismus as well as the 
defect of mobility of the eyes was very probably the result of a thread- 
operation. The operation had given rise not only to a most undesirable 
over-correction of the convergent strabismus, but even to a difference in 
height between the two eyes. The operator had tried to remedy this, as 
was easy to see, by the tenotomy of the right superior rectus, and had thus 
complicated the over-correction in the horizontal plane by a more con¬ 
siderable, and still more disfiguring, vertical deviation. 

The primitive strabismus having dated from the patient’s early in¬ 
fancy,—that is to say, from an epoch when binocular vision^vas not well 
established,—diplopia did not exist. The right eye v^Cf^peropic by 
two and one-half dioptrics, and possessed visual acuity from 0.2 to 0.3. 
The left eye had 0.6 of normal vision, after the ctfra^tion of its myopic 
astigmatism of one dioptry. 

I tried to obtain the correction of the ^tfrc^ent strabismus by the 
advancement of the internal rectus, comumaaVvith the tenotomy of the 
external rectus of the left eye, and the c^jrection of the vertical strabismus 
by the advancement of the superior red^fc, primarily set back, of the right 
eye, combined with the tenotomy d0Jie inferior rectus of the same eye. 

In spite of the powerful of these four operations, there still 

remained a certain degree^SSnvergence and of lowering of the right 
eye. Several weeks latei ■medied these defects by the advancement of 
the internal rectus of eye and the tenotomy of the superior rectus 
of the left eye. ♦ 

Let us also q#T5^£ne observation of a strabismus sursum vergens trau¬ 
matic in origh^N. This case was operated on very successfully by Dr. 
Eperon. 1 

A man, ibrty years old, had received a blow from a cow’s horn in the 




Eperon, De la correction operatoire des deviations oculaires verticales, etc., Archives 
almologie, 1889. 



superior internal region of the orbit, opposite the pulley of the superior 
oblique. This muscle was paretic, and a vertical diplopia of twelve degrees, 
homonymous by one degree, was the result of its enfeeblement. Binocular 
vision was retained over only a very restricted extent (Fig. 32a), com¬ 
mencing about the twentieth degree above the horizontal and going to the 
upper normal limits. 

Eperon performed the advancement of the inferior rectus of the affected 
eye, and thus obtained, at the end of only two weeks, a field of binocu¬ 
lar vision represented by Fig. 32 b. It will be seen that the fusion of the 
images of the two eyes is restored over all the useful extent of vision, 

Fig. 32&. 

Fig. 326. 



This observation is a striking examjjde^&l^he advantage which muscu¬ 
lar advancement has over tenotomy. ^J\Vfmall find additional evidence of 
the same fact when considering the W" lent of non-paralytic strabismus. 

r muscle dates from the earliest years 
the head may simulate veritable torti- 

Cases ot this sort, tcv^Kfch 1 have given the name of ocular torticollis , 
have been reported ^y feuignet, 1 Wadsworth, 2 Risley, 3 Morosow, 4 Nieden, 5 
Lowett, 6 B radfonU am myself. 8 

1 Cuignet, Reci^^thoplitalmologie, 1873, p. 24. 

2 Wadswortl^llransactions of the American Ophthalmological Society, 1889, p. 381. 

3 Risle^>^^^h. 

4 MorosS^Vrach, 1890, p. 743. 

n, Centralblatt fur Augenheilkunde, November, 1892. 

<pyat, Transactions of the American Orthopedic Association, ii. p. 230. 
Bradford, Centralblatt fur orthpaedische Chirurgie, etc., 1890, No. 9. 
Landolt, Torticollis oculaire, Bulletin medical, 1890, p. 578. 



The optical or operative correction of the visual defect is, as a matter 
of course, at the same time the remedy of this false torticollis, while the 
application of electricity is of no avail, and operations on the muscles of 
the neck, which have been proposed by eminent surgeons, would lead to 
genuine disasters. We cite these cases to show how important it may be 
to recognize a muscular paralysis and to refer anomalies in the direction of 
the head to their real cause. 

It is also very interesting to note in this connection that, inversely, 
in true torticollis, the eyes execute a compensating rotation in the opposite 
direction from that of the face. This rotation, by its persistence, finally 
brings about a weakening of the muscles which turn the eyes in the patho¬ 
logical direction of the face, and whose paralysis could have brought about 
a false torticollis. 1 


In the foregoing section we have considered the ocular muscles, one by 
one, with reference to the movement of the globe which the contraction of 
each produces, when normally exercised, and the phenomena which result 
from the paralysis of the individual muscle. 

Although paralysis frequently affects one single muscle of the eye, it 
scarcely ever happens that a single muscle contracts separately. All the 
muscles are always more or less active in giving the eye its direction and 
in holding it in its position. 

A more nearly correct notion of the ocular movements-p^ idea which 
is more in conformity with reality—will be had by cM^dAing all the 
muscles as together forming one motor apparatus, in^fcfich they combine 
their action in marvellous harmony. Anatomy, bOhowing the muscles 
connected by the capsule of Tenon, the conjund^QsaJ and the intermediate 
cellular tissue into one apparatus, makes >*tfGjRiprehend the fusion of 
their action which gradually goes from to the other without inter¬ 

On the other hand, it can be seen tWt each movement given to the eye 
encounters an opposite regulatina^&vement. To the forces which draw 
the globe into the orbit (the fjM^ecti), nature opposes, besides the sus¬ 
pensory ligament (the diapj^^an of the orbit), the oblique muscles, which 
tend to draw the glota^f^sward. The abductor muscles, of which the 
external recti are the prwrcipal, have antagonists in the internal recti, the 
levators are opposb^JJy the depressors, and their actions are again com¬ 
bined to preve ntJ© globe from making a faulty rotation around the antero¬ 
posterior a^.>^V 

This imitation exists not only for the vertical and lateral movements 
which a«iAso easilv explained by the well-known arrangement of the ocular 

— \ryy --- : — : - 

^ 1 Hiibseher, Beitrage zur klinische Chirurgie, 1893, x. S. 299. 

2 See Landolt, Archives d’Ophtalmologie, 1897, p. 74. 



muscles, but also for the intermediate movements, however complex they 
may be. There is no direction that the eye cannot easily take and in which 
it cannot remain without fatigue. 

Hence it is justifiable to assert that there exists an admirable harmony 
in the action of the motor muscles, since, in spite of their fixed origin and 
their attachment to the globe, six suffice to vary infinitely the movements 
of the eye. 

The mechanism of the motor apparatus, however, will appear more 
marvellous still, when the combined movements of the two eyes are con¬ 

The binocular movements have for their purpose to direct the two eyes 
always simultaneously towards the point to which the individual's atten¬ 
tion is directed. In this way the image of the fixed point is formed 
simultaneously on the fovea centralis of each eye; the two retinal images 
are fused in a single one, and there is single binocular vision. From 
this binocular vision results not only a more vivid visual impression, but, 
above all, the impression of the distance of the point looked at, and the sen¬ 
sation of the “ relief” — i.e., of the third dimension. 

It is easy to convince one's self that, so long as the human species 
has existed, the movements of the two eyes have been associated for the pur¬ 
pose of obtaining this binocular vision. Certain movements which are by 
no means impossible, such as divergence or the raising or lowering of one 
eye alone, have remained in a rudimentary condition simply because bin¬ 
ocular vision never calls for the former, and only rarel^V-that is, only 
during the inclination of the head—for the latter. 

Other movements, on the contrary, have becoqi^o habitual to the 
eyes that they are always made by both togetlufiXas, for instance, the 
raising and lowering. One eye cannot be rai lowered beyond a cer¬ 

tain degree without the other following it^ffaTo the lateral movements, if 
the gaze of the left eye be directed to ^eyirhiament, from left to right, 
from one star to the other, the right|fe will follow it faithfully, even if 
it be covered, and vice versa. \J 

The same is true when the^^et approaches : the eyes will follow it 
by converging. They followi^Q/^ewise when it is withdrawn, by dimin¬ 
ishing their convergence parallelism of their lines of sight, when 

the object has reachecLin^mty. 

Hence there has B^ejJ formed an intimate association between the muscles 
acting in the verUcfipthe levators of the two eyes, and the depressoy's, so that 
similar muscle^y* scarcely dissociate their contraction. 

In th ed^Spntal plane, or, to speak more correctly, in the plane of the 
orbits, at first, the association of the abductors with the adductors in 

the lateraSmovements ; then that of the adductors in producing convergence. 

V^Vyiese must be added the combined action of the abductors, not 
the diminution of convergence and in real divergence, such as is 
^wovoked by means of abducting prisms, but also that simultaneous con- 



traction of the abductors which is indispensable to counterbalance that 
of the adductors. 

This active abduction has been denied, and it has been sought to explain divergence 
solely by the relaxation of the adductors. Convergence would be then deprived of an 
antagonistic function. This is scarcely admissible, in view of the mathematical precision 
with which convergence is produced and maintained. 

Moreover, many of those who deny the existence of active abduction still admit that 
the position of equilibrium or repose of the eyes is sometimes convergence. It may be 
asked, then, how the eyes get out of this-state of repose , if it is not by a simultaneous con¬ 
traction of the abductors. 

It has been urged that, if there exist an active power of divergence, we ought to be 
able to give to the two eyes a divergence equal to the sum of the rotation towards the 
temple of which each eye alone is capable,—that is to say, of from ninety to one hundred 
degrees. Since, “ in spite of exercise,” we succeed in diverging only a few degrees, some 
consider the absence of the simultaneous contraction of the abductors as demonstrated. In 
what, however, consisted that exercise of divergence which should demonstrate anything ? 
It was the application during a very limited time of abducting prisms, to which some 
oculists have subjected themselves. Are such temporary experiments comparable to the 
powerful impulse of convergence which has been in action almost constantly, for the sake 
of binocular vision, during the whole existence of the race? And again, the maximum 
of convergence is much less than double the nasal rotation of each eye alone; the former 
is about forty-two degrees and the latter more than one hundred. 

Why, one might ask, can the internal recti not turn the globes as far in convergence 
as in the movements which are called associated? This is probably because it is not neces¬ 
sary. It scarcely happens that one needs to look at objects three centimetres distant. And 
it is for the same reason—that is to say, because it would be superfluous—that active 
divergence has not been more developed in our race. 

Furthermore, divergence is abolished in paralysis of the external recti muscles, though 
nothing prevents the interni, in this case, from entire relaxation. Finally, there exists 
a form of convergent strabismus, or an insufficiency of divergence, VthXig neuropaths, 
ataxies, or persons enfeebled by debilitating diseases, which finds jS^kpmnation in the 
diminution of the power of divergence and not in a spasm of cmrj^ence. 1 

Although we speak of the association of muscles and of group of muscles of the two 
eyes, it is of course understood that the muscles themselves rfFSySot connected from the one 
eye to the other, but that this connection is found in the that, if it be a question of 

the simultaneous contraction of the abductor of ona^$^Jd of the adductor of the other, 
no one ignores the fact that the impulse starts from\i cjmmon centre of innervation ; that 
if we speak of the simultaneous contraction offcie adductors, or of the internal recti, or 
simply of convergence , we admit, in just the sawiaway, the existence of a centre of conver¬ 
gence, as we believe in the existence of ayentre of divergence, since we admit that the 
abductors can contract simultaneously, 

One evening I was with Charco^Vd^i a colleague timidly suggested that the exist¬ 
ence of a centre of convergence ^^SWoe admitted. The master contented himself with 
a shrug of the shoulders by wa/^roreply, and he was perfectly right. Since the function 
exists, it must have its cent^Hi^ne brain. 

Besides the association of the extrinsic muscles with each other, there 
exists also a verj^ytyortant connection between the motor apparatus and 
the accommqtlmw* apparatus of the eyes. 

The m^^utpparatus suffices, it is true, to direct both eyes simultane¬ 
ously toVaras the object of fixation, and this object is seen binocularly 

bot r ai 


i SMi among others, Uhthoff, “ Ein Fall von Divergenzlaehmung, 
:he Wochenschrift, 1893, Nr. 11. 

etc., Berliner 



when its image is received at the same time by the fovea centralis of each eye. 
But will it be seen distinctly ? This is another question. The distinct¬ 
ness of vision is, indeed, not a function of the motor muscles; it depends 
upon the distinctness of the retinal image, and this depends, in turn (apart 
from the transparency of the refractive media and from the form of the 
refractive surfaces), upon the optical adaptation of the eye. 

This adaptation is, as we know, controlled by the ciliary muscle . 1 Con¬ 
traction of this muscle causes the crystalline lens to become more convex, 
and thus increases the refraction of the eye. When the muscle relaxes the 
lens is flattened and the refraction diminishes. 

We certainly need not be astonished to find intimate relations between 
two functions which, however different anatomically and physiologically, 
are yet always exercised simultaneously, with the aim of securing binocular 
and distinct vision. 

These relations are most easily explained in this way. The standard 
eye is emmetropic , or nearly so . 2 In a condition of repose—that is to say, 
when its accommodation is nil —it is adapted to infinity. In order to see 
binocularly an infinitely distant object,—a star, for instance,—the two eyes 
ought to be directed parallelly : hence in this case convergence is also nil. 

When the object approaches, the two functions come simultaneously 
into play,—the convergence in order to direct the two eyes towards the 
object, the accommodation to adjust their dioptric apparatus to its distance. 

The effort necessary to insure binocular and distinct vision increases 
alike for the two systems in proportion as the object C 0 «^s nearer. It 
is always the same for both in emmetropia,—that i: , for normal 


The connection between the two functions iuO^iestion has in conse¬ 
quence become so intimate that, as Donders shown, one can scarcely 
be used without the other . 3 An emmetm^Qlio converges makes, at the 
same time, an effort of accommodation, when his eyes are made to 
diverge by means of pri-ms, he can^^arcely any longer accommodate. 
The same is true for accommodation, vj^et the emmetrope be made to fix a 
very distant object. Hide the from his left eye by means of a screen 

which, however, will permit observe this eye. Although not seeing 

the object which is fixed^^ie right eye, the left nevertheless remains 
directed exactly to wand same point as its fellow. 

Let a concave glas^he placed in front of the right eye; this lens obliges 
it to make an efftnCjf accommodation in order to see the object distinctly. 
Of course this tfmfrt eye will remain immobile, since the point of fixation 
has not cktTOe**its place; but the other eye will be carried towards the 

1 Lamdort, Refraction and Accommodation, translated by Culver, p. 113. 

^^Aiematical exactness does not exist in physiology. There are great errors, but also 
jros^lnpensations. Biologic phenomena must be considered grosso modo ; otherwise they 
vulnot be understood. 

3 Landolt, Refraction and Accommodation, p. 200. 



nose to an extent proportionate with the strength of the glass. This phe¬ 
nomenon is explainable in a very simple manner. The accommodation 
being always the same in the two eyes, the accommodative effort made by 
the right eye has provoked not only an analogous effort in the other eye, 
but also a proportional effort of convergence. 

On the contrary, if, while looking at a near object, I cover one of my 
eyes, this eye will cease to converge so soon as I furnish the other eye with 
a sufficiently strong convex glass, for this glass renders it unnecessary to 
make an effort of accommodation to see the object distinctly. 

Another conclusive experiment in this connection consists in looking 
through strong abducting prisms at a near object, the vision of which re¬ 
quires at once an effort of convergence and one of accommodation. These 
glasses, without influencing the accommodation, force upon us the alterna¬ 
tive of seeing distinctly,—that is to say, with an effort of accommodation, 
but with homonymous diplopia, because of the convergence which this 
effort necessitates and which is counterbalanced by the prisms,—or of seeing 
singly, by directing the eyes parallelly or nearly so, as required by the 
prisms, but indistinctly, because of the deficit in accommodation, accom¬ 
modation being, under those circumstances, no longer stimulated by con¬ 
vergence. 1 

The converse takes place when both eyes are furnished for near vision 
with convex glasses which suppress the accommodation. In this case, one 
sees distinctly, but with crossed diplopia, because the relaxation of accom¬ 
modation brings about parallelism of the eyes; or singly, bitf indistinctly, 
because the accommodation which accompanies the coiw^n^ice towards 
the near object, by associating itself with the effect of j^J^fconvex glasses, 
increases the refraction of the eyes beyond what is roejWved. 

The relationship which, in the human speci^wnites accommodation 
and convergence, may become so intimate inr€be case of an individual 
who enjoys binocular vision that, withouO^mg absolutely emmetropic, 
but having need of accommodation for ^arwision, he will direct towards 
the point of fixation even a covered ej(ejguided with surprising precision 
by the accommodation which its fel^y exerts in order to see distinctly. 

Without accommodation, the (ukction of the excluded eye is most un¬ 
certain, since nothing tells ^aCprecise location of the point of fixation. 
This point may be at aiw dm^nce whatever on the line of sight of the free 
eye. • It is true that, ifyJiejdistance of the object is otherwise known , the nor¬ 
mal man, by this rgegps, directs towards the point of fixation, approximately , 
his lines of sigh t,^e*^iTithough one of his eyes cannot see the point. 2 Thus, 
when gazing«ai/ft^rffinger, he will converge more or less, knowing that the 
no^^mi infinite distance, but near him. This convergence, how- 

finger is 

1 In-order 

t to become accustomed to relax one’s accommodation,—during ophthalmo- 
scomc^x^nfhation, for instance,—there is no better means than to drect one’s eyes 
pamhdlv to the extent of obtaining a crossed diplopia. 

& Hlansen-Grnt, Fifth International Congress of Ophthalmology, New York, 1876. 



ever, cannot, of course, have the precision which results from accommo¬ 
dation; 1 but it is of interest, as showing that the imagination, correct or 
incorrect as to the situation of the object, may influence the reciprocal 
direction of the eyes. 

Knowing now the relations between the movements of the two eyes, as 
well as the principal factors which preside over their cooperation, we ought 
to ask ourselves what is the direction which the eyes assume when in a condi¬ 
tion of absolute rest ,—that is to say, when they are abandoned to the equi¬ 
librium of their muscles only. As we shall see later, it is not very easy to 
answer this question, because it is difficult to take away from the individual 
all the influences which are capable of modifying the direction of his gaze. 
Inasmuch as even imagination is among these influences, to be sure of abso¬ 
lute repose it is necessary to deprive the person of his consciousness. In 
this state, in syncope, in narcosis, in death, divergence of the eyes is the 
rule. This is nearly always the case also in double amaurosis. Two blind 
eyes almost always diverge. 

Experiments made on persons who are asleep have likewise demon¬ 
strated that, when abandoned to the free play of their muscles, the eyes 
rarely converge; they oscillate about parallelism, and almost always take a 
more or less divergent direction. 

Thus the eyes normally diverge in a state of rest, but without an appre¬ 
ciable difference in height 

This fact need hardly surprise us. In the first place, the orbits, those 
cavities in which the eyes develop and move, diverge vert appreciably,— 
from forty-two to forty-four degrees. 2 Let us next ijetGujhe disposition 
of the external recti muscles. They are rolled on^^e ocular globes as 
if they had been forcibly obliged to follow tMjj^ as convergence de¬ 
veloped, under the impulse of binocular visimiO^ privilege of a superior 

race. 'Cj* 

We must not forget, indeed, that tlfisjiraultaneous contraction of the 
adductors is a movement which is notfe Deinet among the lower mammals, 
and that it is produced in man only(^ the interest of the vision with both 
eyes, synergetically with an eff^lj of accommodation, or, as we shall see 
later, under the influence of^(p^idiar disturbance of innervation. 

We ought not, then,i 
selves, assume a sommykSlj 

the formation of thd^splcies, and diverge more or less. 

astonished if the eyes, abandoned to thern- 
5 \kimilar direction to that which they had prior to 

Whenever^^h eyes are not simultaneously directed towards the point 
to which^flCNpossessor directs his attention, strabismus is present. 

StrSi^mlis is, therefore, especially liable to occur when binocular vision 

dolt, Seventh International Congress of Ophthalmology, Heidelberg, 1888; and 
i^rcmv fur Ophthalmologie, xxxv. S. 265. 

\/ 3 Merkel, Topographische Anatomie, i. S. 237. 



does not exist. We have seen, indeed, that in this case it is only the 
association between accommodation and convergence which can impress a 
proper direction upon an eye which is not fixing. 

If this association is not present, the eyes deviate,—that is to say, they 
obey other laws than those dictated by the interest of binocular vision. 
Their direction, as well as their movements, remain, indeed, subject to the 
associations which we have considered. 

Suppose, for instance, an individual one of whose eyes is amaurotic. Bin¬ 
ocular vision is impossible. It would seem as if the blind and useless eye 
ought to be able to point anywhere. This, however, is not the case. In the 
first place, this eye will not abandon the level of its fellow. Non-paralytic 
strabismus sursum or deorsum vergens is very rare, and never attains a de¬ 
gree comparable to that which one usually meets with in lateral strabismus. 

Hence the eye which does not fix can deviate only in the horizontal 
direction,—towards the temple or towards the nose. Observation seems 
to justify this supposition by showing non-paralytic strabismus as almost 
always divergent or convergent Thus, one often finds in text-books the 
statement that an amaurotic eye turns away from its fellow in diverging, or 
aids its fellow in the latter’s accommodation by converging. 

Tliis conception of strabismus is, however, not entirely correct. 

For the same reason that one eye never moves alone, so it cannot de¬ 
viate alone (unless muscular paralysis be present). Hering has very justly 
pointed out that, even in the special case when the movement of the object 
viewed seems to require rotation of only one eye, the other takes an active 
part in the motion. Let the object of fixation approach or r^fc^P along the 
visual line of one of the eyes; though the other eye alone^Jhis obliged to 
change its direction in following the object, the musclejjroWhe eye which is 
apparently immobile nevertheless accompany the con-ration of those of the 
moving eye. When the object comes nearer, bouN^mrnal recti contract as 
a result of the same convergence-impulse in the case of the eye 

directed straight forward, the external ractu&^Joy its contraction, prevents 
the eye from being carried towards the/n^e and holds it in its position. 
The opposite takes place when the convergence relaxes in proportion to the 
recession of the object. 1 (lw 

Something analogous hapnens in*3iat kind of strabismus with which we 
are at present occupied. ThgJ^v^ no divergence of one eye, as in paralysis 

1 It is known that duriiT^^nvergence the eyes are not only carried inward, but 
at the same time undergo a^kght rotation around the line of fixation. (See, among others, 
our experiments, Aubei*v^U'siologische Optik, in Graefe und Saemisch, Handbuch der 
gesammten Augenhpi^nde, ix. S. 660.) 

It is easy IJ^^erve by means of our dynamometer that, when the object fixed is 
brought alon^^^usual line closer to one of the eyes, so that only the other eye appears 
to move, th4 eyk which is apparently immobile executes the same rotation around its 
antero-w^st^rior axis as its congener. The luminous line of the instrument seems to 
separate r^ro two equally oblique lines which at the punctum proximum of convergence 
havcCmy one point in common. 

^>Vol. IV.—6 



of the internal rectus, or convergence of one eye, as in paralysis of the 
abclucens; but there is divergence or convergence between the two eyes in 
the same degree. 

It is evidently always necessary that one of the eyes fix,—that is to 
say, that it be directed towards the object which attracts the attention of 
the individual in such a way that the image of this object shall be formed 
upon the fovea centralis . This gives the appearance of a monocular de¬ 
viation. But in reality we might call non-paralytic strabismus binocular , 
in opposition to the paralytic strabismus with which only the affected eye 
is concerned. 

Hence it would not be proper to say, in a case of strabismus of the left 
eye, that this eye diverges or converges; to express one’s self correctly, one 
would need to say, the eyes diverge or converge , the right eye performing the 
fixation . 

The proof that this way of considering non-paralytic strabismus is cor¬ 
rect consists in the fact that whichever eye is used for fixation, the excluded 
eye always deviates through the same angle . There is not, as in paralytic 
strabismus, a secondary deviation due to the difference in innervation to 
which the two eyes are subject. 

The angle of non-paralytic strabismus remains also apparently the 
same during the lateral movements. Hence the term concomitant strabis¬ 
mus which is applied to this form of squint. 

It has also been called muscular strabismus . This name is ill chosen, 
as we pointed out many years ago. 1 It might, indeed^lcad to the suppo¬ 
sition that this form of deviation of the eyes was changes in the 

structure of the muscles. If the ocular muscles jm^^ipate in the evolution 
of concomitant strabismus, they almost always only secondarily. 

Strabismus is not always manifest In if|^arly stages, especially, it 
sometimes remains latent , and shows itsqtfyttly under certain conditions; 
for example, in consequence of fatigue^f^tra eyes or of the body generally, 
under the influence of emotion, or, l^ove all, when binocular vision is sup¬ 
pressed by the exclusion of one e}^^ 

Nothing is more instructi^tlian to study the direction which the eyes 
take under such circumstauj^m Eyes that are otherwise well directed, by 
virtue of the power of^jra^lmpulse to binocular vision, sometimes diverge 
or converge as soor object of fixation is hidden from either of them. 

Frequently aL^^^pecially at the outset, the deviation is not permanent . 
There exist iyt^pials when the most precise examination reveals no anomaly 

1 La«d^roTEperon, Mouvements des Yeux, in De Wecker et Landolt, Traite com- 
plet, 869. See also Krenchel, Archiv fur Ophthalmologie, xix. 1873, S. 142; 

Parinafc^ Annales d’Oculistique, 1891 and 1892; Hansen-Grut, Transactions of the Inter¬ 
national Congress of Medical Sciences, Copenhagen, 1884; Bidrag til Laeren von Skelen, 
VTVciVk ophthalmologisk Tidsskrift, 1889; Transactions of the Ophthalmological Society, 
x*1889, p. 1; Helmholtz, Festschrift, 1891, S. 69; Berry, Diseases of the Eye (1st edition), 
p. 629; Ophthalmic Review, 1893, p. 285. 



in the direction of the lines of sight, while at other times there may exist 
a very evident deviation. In such cases the strabismus is called inter¬ 
mittent or periodic . 

When the vision of each eye is good, strabismus often passes from one 
eye to the other. Without the fixation-object being hidden from either, 
sometimes it is one and sometimes the other eye which deviates. This 
alternation of the strabismus might appear surprising; for, while it is 
quite natural that an amblyopic eye may deviate without producing any 
visual disturbance, it is not easy to understand how a person whose eyes 
are not both directed simultaneously towards the object of fixation does not 
see double. 

The absence of diplopia is one of the characteristic signs of concomitant 
strabismus. Yet the statement made in manuals that double vision is 
never present in this form of squint is not accurate. If pains are taken, 
one can almost always cause the patient to perceive the image received 
by his squinting eye simultaneously with that of the other eye. For this 
purpose a red glass is placed in front of the better eye. The patient is 
made to look at a distant candle-flame, and the eyes are alternately covered 
and uncovered for a certain time. Thus, one seeks to cause the patient to 
perceive separately, then simultaneously, the two differently colored images. 
If there is difficulty in perceiving one of the images, the screen should be 
made to pass in rapid succession before the eye usually employed for fixa¬ 
tion, in'order to diminish the intensity of its vision. 

On the other hand, one may seek to provoke diplopia, primarily in the 
vertical meridian, by means of a prism which carries the inWk of the ob¬ 
ject of fixation above or below the horizontal meridian retina. If 

the vision of the deviated eye be at all sufficient, the part&m will promptly 
appreciate the fact that he sees two objects, not only is&na vertical interval, 
but also separated laterally. However, that wjH^Alistinguishes the di¬ 
plopia of concomitant strabismus from the dipWk* accompanying paralysis 
of the ocular muscles, is not only the difficiVlijf experienced in provoking 
it, but still more the impossibility of determining its exact degree . Although 
seeing double, the patient seems to prcfi^cVtlie two images to the same place ; 
sometimes he can hardly appreciato^KAher his diplopia is homonymous or 
crossed. It is as if he were ccms©atwrof the false direction of his eyes, and 
made the correction of it en&^into the projection of his retinal images. 
The victim of paralytic rfrakismus, on the contrary, projects absolutely as 
if he did not squint,—tlntr is to say, as if the direction of his eyes corre¬ 
sponded to the normafrQnervation of their muscles. 

Apart from tkAj^ecial conditions which we have just mentioned, the 
vision of the^J®&t ( >f fixation remains single. The image received by the 
deviating e)i^ems to be systematically disregarded by the visual centre, 
which renters only the image received by the healthy eye. 

j\Jbasy .to represent to one’s self this phenomenon, which has its 
analq^Lie in the domain of physiological facts. Whoever practises micro- 




seopy (or ophthalmoscopy) with both eyes open knows that the attention 
may be concentrated on one visual field to such a degree as entirely to annul 
the perception of the visual field of the other. He equally knows that 
voluntarily he can perceive the macular impression of either eye. He may 
even perceive simultaneously the different images formed on the maculae 
of the two eyes. This happens, for instance, in microscopic work, when 
one eye is used for the examination of the object and the other is employed 
to sketch it. 

Something analogous may be observed in certain cases of strabismus, 
especially when the deviating eye possesses a fairly good vision. If the 
image of a well-defined object be produced upon the macula of the devi¬ 
ating eye (especially if one directs the individual’s attention to the object), 
the visual impression of the other eye sometimes fades before that of the 
squinting eye does. At times also one succeeds in making the patient per¬ 
ceive the two objects simultaneously. Curious to say, when the two objects 
are similar,—for instance, two candle-flames (one of which may be colored 
by a glass),—their macular images are not always fused into a single image. 
The patient passes rather from monocular vision into diplopia. 

The phenomenon of “suppression” or of “exclusion” of the images re¬ 
ceived by the deviating eye has nothing about it, therefore, which ought to 
be surprising. It is all the more natural since this defect in binocular 
vision occurs at an age when this function has not yet acquired its entire 
development, and when it is, therefore, readily susceptible to modifications, 
as is true of all the other functions of the central nervoufc system. 

Between diplopia as it manifests itself in par^raic) strabismus and 
the absolute suppression of the images received bv^e deviating eye, exist 
different intermediate categories, representing sqmatay stages in the process 
of exclusion which we have just discussei^^here are, indeed, persons 
affected with strabismus in whom lateral {jttHtapia can be provoked only by 
interposing before one eye a prism in^^Nnorizontal direction. The dis¬ 
tance between the double images th(^received corresponds to the angle of 
strabismus, increased or diminishe(Q^y the deviation produced by the prism. 
The suppression of the visual ^S^iction occurs, therefore, only for a limited 
area of the retina, situatedjjgween the fovea centralis and that part of the 
retina on which the in|&rcu#f rhe object of fixation is formed. This phe¬ 
nomenon is designthe term regional exclusion . 

In other caselCof regional exclusion the localization of the retinal 
impression o£ tfe deviating eye is much more uncertain. The distance 
between the>hh%*1mages varies, and no longer corresponds to the sum of or 
the diff^r^ft^between the prismatic and the strabotic deviations. 

'M^^kjon of exclusion may grow larger, beyond the limits above 
mentioned, and it is always more extended in the horizontal than in the 
^yerabal direction. Weak vertical prisms often suffice to provoke a corre- 
V sending diplopia, while sometimes, even in the absence of compensating 


^movements of the eyes, very strong horizontal prisms are necessary for the 



doubling of the image of the point of fixation in the horizontal direction 
(horizontal exclusion). Again, exclusion may take place over the entire 
retina; diplopia cannot be obtained by any means. This is the total exclu¬ 
sion which actually corresponds to the absence of binocular vision. 

In addition to these diverse alterations of vision, we find not rarely 
that a kind of new identity between the two retinae is established. The part 
of the retina of the affected eye which receives the image of the object 
looked at by the normal eye assumes, as it were, the function of the macula. 
It becomes the centre of orientation for the squinting eye. Its visual 
impressions may even be fused with those of the macula of the healthy 
eye. In this case weak prisms suffice to produce diplopia. If, on the 
other hand, by means of prisms or suitably placed mirrors, we cause the 
image of an object to fall simultaneously upon the fovea centralis of each 
eye, instead of fusing the two images, the patient manifests diplopia, and 
the distance between the two images corresponds to the degree of the 

The same thing occurs in these cases after successful operation for stra¬ 
bismus. The eyes being now directed normally, instead of binocular fusion 
of their macular images a marked diplopia—one of the same degree as, but 
opposite to, that of the former strabismus—is manifest. For instance, if 
we have by an operation corrected a convergent strabismus of twenty-five 
degrees, the patient may manifest a crossed diplopia of the same amount. 
If we have corrected only twenty degrees, leaving five degrees of con¬ 
vergence, the diplopia will be of twenty degrees. \ 

We consider this change in the correspondence of the re^sg qf the two 
eyes as a consequence of the long duration of the strabis^s^ and not as 
congenital, as has been alleged by some who have trtec^Q explain by it 
the deviation. Observation proves, indeed, that "the correction of 

the squint the diplopia produced by the change itfyBe reciprocal direction 
of the two eyes almost always disappears. > 

As to the sense qf depth, or of the third i^mension, in strabotic patients, 
the investigations which have been madd^ith Hering’s experiment show 
that, in the immense majority of ca^d0persons affected with concomitant 
strabismus are incapable of correedj^ydging where the balls fall. 

One sometimes succeeds in giwng the strabotic person the impression 
of “ relief” by means of die stereoscope. For this, however, it is essential 
that the vision of the devS^i^g eye be not too low, and that the patient be 
willing to undertake, ♦p^kntly and methodically, the necessary exercises. 

Stereoscopic fusj^ywith impression of the third dimension may in 
cases of strabismmQ^e so intimately interlinked with a permanent deviation 
that it is soiuraw^ suppressed by the straightening of the eye. (Nagel, 
Schoeler. 1 ) v[t niav exist without there being binocular fusion in ordinary 
- - 

iJ^agel, Das Sehen mit zwei Augen, 1861; Schoeler, loco citato. See also R. Greeff, 
Monatsblatter, 1895, S. 352. 



vision, as has been demonstrated by means of Hering’s experiment; this 
is a consequence of the fact, discovered by Schoeler, that the stereoscopic 
impression may result from the fusion of images formed on regions of 
the two retinae, which do not correspond. 

In any case, one succeeds with most strabotic persons, when the de¬ 
viating eye is not too weak, in causing to be perceived simultaneously, or 
even to be fused, the two components of a stereoscopic image. 

Whatever may be the gravity of the changes undergone by binocular 
vision, the deviating eye is, however, not entirely lost to the patient; it 
contributes, at least, to extend the field of his vision. 

When the deviating eye has sufficient vision and is used temporarily 
for fixation, it generally projects correctly the retinal images that it receives, 
the sensorium being conscious of the abnormal direction of this eye. 

It happens, on the other hand, in cases of inveterate strabismus, that 
when the good eye is occluded the squinting eye is very imperfectly or not 
at all straightened, and that it nevertheless projects retinal images as if it 
were normally directed. This phenomenon is only the corollary of that 
which has been mentioned when speaking of the fusion of an eccentric 
image, received by the strabotic eye, with the macular image of the other 
eye. The two observations show that an eccentric part of the retina may, 
in the deviating eye, gradually acquire the functions of the macula and 
become the centre of orientation for this eye. 

Yon Graefe, Javal, Nagel, and the author have dted cases wherein 
the defective eye projected its retinal image simultaiqrf^ly in two different 
ways: in one way as if it were affected with paia^Ntflc strabismus, that 
is to say, as if the eye supposed itself to be normal position; on 

the other hand, correctly,—that is to say, a«SCthe part of the retina on 
which the image falls had taken the placeS^tne macula and corresponded 
to that of the other eye. It followrfTffi^in such cases there would be at 
once binocular vision and diplopi^L 'T-nueed, one of the projections of the 
deviating eye is confounded withyhat of the healthy eye, while the other 
is separately perceived. It ^leRmes even happens that the three images 
are perceived each by itsel^Jw that the P atient claims to have a g enuine 
triplopia. A0 

We shall rec tjtese peculiarities of the vision of strabotic persons 

when we come tcQjijbtfss the surgical correction of ocular deviations. 


nus .—The fact of the frequency of con- 

>pes, especially in the medium degrees of 
trkable researches of Dondcrs, known to 
ysiologist explained this fact by the rela- 
ccommodation. Hyperopes, he says, are 
mmodation in order to remedy the insuf- 

Tliis effort of accommodation among 



those whose relative amplitude is not especially developed of necessity entails 
an excess of convergence. 

This phenomenon is still more easily produced when the hyperope looks 
at a near object the fixation of which in his case requires all the stronger an 
effort of accommodation. To this greater quota of accommodation corre¬ 
sponds a still more exaggerated amount of convergence. Hence the ten¬ 
dency among hyperopes to a pathological convergence. 

It is evident that this excess of convergence cannot manifest itself 
simultaneously in both eyes ; otherwise neither of the lines of sight would 
be directed towards the fixation-point, unless the head executed a rotation 
equivalent to that of the fixing eye in the opposite direction. In reality 
this rotation occurs only in the minority of cases, when it gives rise to a 
peculiar position of the head. For the most part, the better eye appears 
straight in relation to the face, whilst the other is turned towards the nose 
at an angle corresponding to the nervous impulse affecting the adductor 
muscles of both eyes. 

There occurs in this case a phenomenon analogous to that which we 
have described before, when the object of fixation approaches from infinity 
along the line of sight of one of the eyes. The innervation necessary to 
keep the eyes directed upon the object is equally divided between the mus¬ 
cular apparatus of the two globes, but it produces an effect different from 
symmetrical convergence. In one of the eyes it maintains, so to speak, the 
equilibrium between the abductor and adductor muscles; in the other it 
affects especially the adductor, which brings about an angle of convergence 
double that which would be necessary if the fixation-poip4^jwere on the 
median line,—that is, if the convergence were symmetrical.- x)nly in this 
latter case, in which the nervous impulse distributed^) the muscles is 
exactly proportionate to the distance of the fixation^&^ect, the two lines of 
sight cross at that object; in the case of conv< strabismus, in which 

this impulse is exaggerated, the two lines cross between the eyes and 

the object. # 

An example will make the matter etyr. Suppose a young emmetrope 
to fix an object situated one-fourth of jrluetre in front of him. He makes 
an effort of accommodation amouwfeg to 4 D., and a corresponding effort 
of convergence of four for each eye, the object being situated 

on the median line. 1 


1 We have described onqsage 185 of our treatise on refraction the ingenious method 
which Nagel has devisedtlj express the degree of convergence as well as that of the refrac¬ 
tion or accommodatio/F^W&gel takes as the unit of measurement for both functions the 
metre , and call$ tfft^llgle of convergence necessary to each eye to fix a point situated at 
one metre fr«^iA^n the median line a “ metre-angle The “ metre-lens,” or dioptry , 
represents tns^fraction required in order to see distinctly this same point at the same dis¬ 
tance. fri^emmetropia this refractive power is furnished by the accommodation. 

r Eto^|n^'t being, for both functions, greater in proportion as the object is nearer, it 
ma^Ube considered as inversely proportional to the distance between the object and the eye . 

Point situated at one-half of a metre on the median line will require of each eye, in 



In this way he is exactly adapted to the distance of the object, and his 
two lines of sight intersect at the object. 

None of these conditions has changed when the object leaves the median 
line and is carried directly in front of, say, the right eye. The left eye 
then furnishes eight metre-angles of convergence, while the right has its 
line of sight parallel with the median plane. This is not equivalent to 
saying that the innervation is unequally distributed to, the muscles of the 
two eyes. Only, to the impulse necessary to convergence for one-fourth of 
a metre is joined the effort necessary for associated movement, which has 
carried both eyes to the right. Hering shows that the right eye has re¬ 
ceived the same impulse to convergence as the left. The rotation around 
the antero-posterior axis is the same for both eyes, though one of them 
seems to remain in the primary position, while the other presents the appear¬ 
ance of an exaggerated adduction. 

if, in the emmetrope, we screen off the fixation-object from the left eye, 
it still continues to be directed to the same point as its neighbor, even 
if the position of the object be changed. The reason of this is that in 
emmetropia the accommodation is equal to the convergence, and therefore 
both eyes remain directed to the same point even when binocular vision is 
not present. If now a concave glass is placed in front of the right eye, 
distinct vision can be obtained only by an effort of accommodation. It 
will then be found that, while the right eye has remained immobile, as the 
fixation-point has not been changed, the other eye has been turned inward. 
The stronger the glass, the more is the left eye rotated tojvtoxds the nose. 

Accommodation is always the same in both eyes, the accommo¬ 

dative effort in the right eye causes not only a similaj0ffiort in the left, but 
also brings about a proportionate degree of contfpqgbnce. If the concave 
glass is one of three dioptries, then the eflSmQjr accommodation will be 
three dioptries, and the convergence used^rfr be three metre-angles for 
each eye. Since, however, it is necessityjn»t one of the eyes—the right 
in our example—be directed towarafi tne object which is occupying the 
patient’s attention, the convergence^^ appear to affect only the excluded 
eye. In the case we are discuss^^, the left eye will be turned towards the 
nose six metre-angles while t^gSpther looks at a distant object through a 

es while tin 

concave lens of three dkltoM^s.^ The same or nearly the same thing oc¬ 
curs in hypermetrooj 4,0 s hypermetropic eyes may be considered as emme¬ 
tropic eyes to whicl^ojicave lenses have been applied. 

Let us tal^e case of a young hyper ope of three dioptries, and let us 
suppose that Adulation between accommodation and convergence is the 
same with Iih^as with the emmetrope. In order to accommodate for a 
dista nq^S^ one-quarter of a metre, our hyperope brings into play not 

be seen single. 

1 m 


: 2 ma of convergence, and, in order to be seen distinctly, 2 

^dioptries of refraction —that is to say, of accommodation —when the eyes are emmetropic. At 
/^X^ne-sixth of a metre the convergence will be Gma, the accommodation 6 D., etc. See p. 130, 



only. 4 , but 3 + 4 = 7 D. of dynamic refraction. To these 7 D. corre¬ 
spond 7 ma of convergence. If both eyes executed each 7 ma of conver¬ 
gence, the two lines of sight would intersect at 1^, or 14 centimetres, 

that is eleven centimetres nearer the eye than the fixation point, and the 
object would appear double. But the hyperope will place the object, by 
preference, directly in front of one of his eyes. He will make over to the 
other eye all the convergence, which in our example would amount to 6ma. 
Thus, while the fixing eye has a normal direction, the other will have a 
convergence of 6ma, equal to about eleven degrees. 

It is true, as might be expected, that the relation between accommo¬ 
dation and convergence is not an absolutely fixed one; otherwise every 
ametrope would have to choose between two alternatives: either to see 
distinctly but double , because of the defective direction of his eyes, or to see 
singly but indistinctly , the normal direction of his eyes excluding perfect 
optical adaptation. 

A certain latitude exists, therefore, as Donders showed, between accom¬ 
modation and convergence, a latitude to which he has given the name of 
relative accommodation and convergence. 1 The hypermetrope can accommo¬ 
date more, the myope less, than the emmetrope, with the same degree of 
convergence. It is for this reason that ametropes are by no means all 
doomed to strabismus. 

This “ relative” amplitude of accommodation and convergence, however, 
has its limits. The hypermetrope of a certain degree may with difficulty 
succeed in furnishing the excessive amount of accommock^fml required by 
his ametropia, while he maintains convergence equal toJ£&oi the emme¬ 
trope. If the sight of one eye, then, be feeble (eithei^^tccount of opacity 
or irregularity of curvature of the refracting surfae&y or of changes in the 
fundus) to such a degree that the image receiye^Nj^that eye may be easily 
disregarded, the patient is in danger of a strabismus. In fact, 

the diplopia which would otherwise havtu’e^rirecl from the abnormal direc¬ 
tion of his eyes causes no inconvenientrtlxHnce the image of the amblyopic 
eye cannot enter into competition toWi the clear and distinct image of the 

other eye which possesses a good 
towards the object fixed. 2 v J 

il acuteness and is directed normallv 

1 Landolt, Refraction aiid i^TH^hmodation, p. 196. 

3 At the very time of wfiting fiiese lines we have observed a case which is very conclu¬ 
sive of Donders’s theory of Histiology of convergent strabismus. 

A girl twelve yet^S^d was brought to us by her parents. Her fine-looking and 
well-directed eyes pi/s£yVed exteriorly and interiorly no perceptible abnormity. One of 
them, however,—scarcely sees at all. It is only by chance that this fact has been 
discovered. O^^J^ation was upon the inferiority of the left hand to the right. The child 
took part in H^oiscussion, and, already reasoning after the manner of adults who like to 
generaliz^Aiid, u That is not surprising, since the left eye does not see either.” Of course, 
her cdWpkmfns were astonished. The eyes of all were examined. Everybody saw well 

wiA^h^Ieft eye, excepting the child in question and-her father. 

to the father’s inability to see with the left eye, nobody was surprised, since one 



This “ suppression” of the retinal image of a wrongly directed eye, 
however, may be acquired by perfectly healthy eyes, if the patient does not 
succeed in dissociating accommodation from convergence in order to gain 
distinct vision. In such a case the strabismus is, to begin with, alternate, 
passing from one eye to the other, until it finally permanently involves the 
eye whose image the patient can the more easily disregard. 

On the other hand, the relations between accommodation and con¬ 
vergence may be suddenly disturbed, as, for example, in paresis of accom¬ 
modation. Here there is no time for the establishment of new relations 
between the two functions; the extreme nervous impulse required by the 
accommodation reacts on the convergence, and convergent strabismus may 
be established. 

Donders pointed out and explained this phenomenon of convergent 
strabismus following a sudden diminution of the amplitude of accommoda¬ 
tion. Thus, it is not rare to see the deformity in question appear in con¬ 
sequence of the weakness of accommodation caused by diphtheria, not only 
in hyperopes whose refraction error is of medium degree, but also in 
liyperopes of less degree and in emmetropes. A large proportion of the 
children who are affected by convergent strabismus present a puny appear¬ 
ance which indicates muscular debility, in which the ciliary muscle may 

Convergent strabismus being most often the result of hyperopia, one 
might suppose that its frequency would increase with the degree of the 
ametropia. This is, however, not the case. The largest contributions to 
this form of squint are given by hypermetropes of averse degree. Don¬ 
ders has explained this fact in the following way. tf\aa we have seen, 
slight hypermetropes escape strabismus, thanks to modification in the 
relation between their convergence and accommoffi&Km in the interest of 
their distinct binocular vision, hypermetropes^O^gh degree do not squint, 
because even the strongest converging efftw^^mld not suffice to call forth 
the amount of accommodation requiredL | bj' their ametropia and by the 
position of the object, especially if vision has to be maintained for 
some time. They, therefore, do noWattempt to make an effort of con¬ 
vergence which, no matter how nrag^erated, could bring them no advantage.' 

Convergent strabismus teW$g/to diminish as age advances to such an 
extent that it is rather after the age of forty, and often passes off 
spontaneously. Thi^ta^is not surprising, for we know that the static 
refraction of the eve\«ereases during the first twenty-five years of life; 

of his eyes l^^/Wrays squinted , and it is even popularly known that badly directed eyes 
see badly. 

Exarn\Svon of the refraction revealed the curious fact that the child was emmetropic, 
while Ijekfather was strongly hyperopic. Though both persons were victims of congenital 
amhj^pu^of one eye, it is only in the case of the hyperopic father that this infirmity has 
fcasKmed strabismus. It has not been transmitted to the child, whose blind eye has been 
kctly guided by its emmetropic fellow. 



myopia augments, emmetropia frequently changes to myopia, hyperme- 
tropia diminishes in degree ; it may become emmetropia or even myopia. 
We do not wonder, then, when we find less convergent squint among adults 
than among children, who are more frequently hypermetropic. It is true 
that accommodation becomes more and more difficult with increasing years, 
while the convergence remains practically the same. One might, therefore, 
suppose that the assistance required by the former of these functions from 
the latter would become greater and greater; but the individual apparently 
accustoms himself to associate a stronger and stronger accommodation 
quota with the same quota of convergence, especially when the instinct of 
binocular and single vision is very powerful. Whatever the explanation, 
it remains certain that there are factors exercising a favorable and control¬ 
ling influence on the relation between accommodation and convergence, thus 
tending to prevent the development or favor the disappearance of a con¬ 
vergent squint. These influences grow stronger with each additional year 
of age. What they depend on we do not yet fully know; they may be 
connected with the central orgau, with the development of the orbit, with 
the motor apparatus and the eyeball, or with all these factors together. 

The hyperope, who squints when looking at objects close at hand, does 
not necessarily present convergent deviation during distant vision. This 
fact may be explained as follows. Let us take a hyperope of 3 D., four¬ 
teen years old. Assume that he has an accommodation of 15'D., con¬ 
vergence power amounting to 12ma. 

The following table indicates the respective quotas of convergence and 
accommodation brought into action when the object of^^fti|>n is gradually 
brought nearer. Jtr 

Fixation at 

Dioptries of 

ma of Con¬ 

Quota of Ac^ 

Wjima of Con- 

Ratio of Quota of 
Accommodation to 






Quota of Conver¬ 



1 rn. 







1 : 0 

1 : 0.3 

\ m. 




’> % 


1 : 0.5 

i HI. 



1 : 0.6 




T 4 2 

1 : 0.7 


If one studies th\£g|ations between the two series of quotas, one sees 
that, for the hypef^e, the quota of convergence increases more and more> 
relatively to thatT^the accommodation , as the point, of fixation approaches . 
A similar< for the emmetrope would show that this relation remains 
constant'$\i.25 in our example), while in myopia the quota of con¬ 
verge^ aiminishes relatively to that of the accommodation, under like 



1 Landolt et Eperon, loc. cit., p. 885. 



Hence there is nothing astonishing in the fact that a hyperope may not 
squint when looking far away, while one of his eyes will deviate inward 
during the fixation of near objects, or that a convergent squint increases 
under the same conditions. 

Furthermore, it is probable that the hypermetrope rarely accommodates 
enough to neutralize all his hyperopia when looking at a distance. Near 
vision that is to say, the vision for working—requires greater distinctness, 
and therefore demands a greater accommodative effort. 

In taking equally into consideration not the absolute value, but the 
quota of convergence and of accommodation, and in comparing them in 
emmetropia and in hyperopia at different epochs of life, one finds that for 
the hypermetrope the effort of convergence to be associated with that of 
accommodation diminishes with the age. This fact, along with those men¬ 
tioned above, might help to explain the diminution and disappearance of 
convergent strabismus with increase of years. 

The convergent strabismus of hyperopes, which is the type of conver¬ 
gent strabismus, is, therefore, according to Donders’s explanation, a spastic, 
an active strabismus. Just as it is seen to increase as accommodation in¬ 
creases during the fixation of near objects, so it diminishes in proportion as 
accommodation diminishes for distant vision. Hence one might suppose 
that it would disappear entirely so soon as the ciliary muscle ceased to 
contract.' Those who claim that, in the absence of any fixation-object, when 
the gaze is said to be vague, the accommodation must be at rest, are aston¬ 
ished to find that convergent strabismus, nevertheless, frequently persists 
under such circumstances. The explanation of this faqt i&Hjowever, not 
difficult. It is indisputable that young hyperopes ha\y*pre greatest diffi¬ 
culty in ridding themselves of at least a slight deej^Nff accommodation. 
They accommodate more or less, even when thei»-St*ze is not fixed upon 
any special object. This latent accommodativp>^©!5rt suffices to maintain 
convergence of the lines of sight. / 

Genuine repose of the nervous imfuiRe/ is obtained only by sleep, 
whether normal or provoked by ana^^tics. Under these conditions 
young hyperopes stop squinting in tire, early stages of the affection. (Stell- 
wag.) The influence of mydriat.i^Vs no less conclusive as to the etiology 
of this form of strabismus, ^^tefr convergent strabismus is not invet¬ 
erate with hyperopes, it eerys during paralysis of the accommodation. 
The ingenious theory c^t^e Dutch physiologist is thus once more con¬ 

One is temptodA^gay that this theory explains only too well the con¬ 
vergent strabi^rqflS^W hyperopes. Indeed, one may wonder why all hyper¬ 
opes, at lea^ft^Nue category that we have pointed out as peculiarly liable 
to this infirmity, do not squint; and, on the other hand, why some indi- 
vidual^Jfi'pjten to contract convergent strabismus without being hyperopes. 

^heVeiulenoy to binocular vision which is innate in our species, on the 
jer Wl, and the comparatively lax and always changeable relations be- 



tween convergence and accommodation, on the other hand, explain suf¬ 
ficiently the immunity of those who escape strabismus. 

As to the others,—those who become strabotic,—we must seek the 
factors which favor the production of strabismus in the circumstances 
which entail the development or facilitate the sacrifice of binocular vision, 
or, again, in the factors which directly favor convergence. 

Binocular vision is more certainly developed and maintained in propor¬ 
tion as the vision of both eyes is more nearly equal and more nearly per¬ 
fect. Whenever one eye is very inferior to the other, whether in conse¬ 
quence of ametropia , or of opacities of its dioptric media / or of change in 
its fundus , or of congenital amblyopia , this eye is of but slight importance 
in the concurrent action of the two; the impulse to binocular vision will 
never become very powerful, or it may not be developed at all. In such 
cases the eyes are abandoned to other factors that are capable of influencing 
their reciprocal direction. Hyperopes are oftenest the victims of conver¬ 
gent strabismus. 

This infirmity, however, may exist, even in the absence of the auxiliary 
causes that have just been pointed out, in the case of eyes whose visual 
acuity is equal. 

When it goes back, as is most frequently the case, to the first years and 
even to the first months of infancy, one has no reason to be surprised that 
binocular vision is incapable of maintaining a proper direction of the two 
eyes. A fortuitous circumstance which may but transiently exclude one of 
the eyes from vision may suffice, at that period, to teach the hyperopic child 
to squint. 

On the other hand, there have been called in, to exjmfo Ihe production 
of convergent strabismus among hyperopes as welL asulmong emmetropes 
and even myopes, circumstances which facilitate cmmi'gence. 

Thus it is that Bonders 2 claims an exces&i^positive value of the angle 
alpha (the angle comprised between the^isQl line and the axis of the 
cornea) 3 as facilitating convergent strahisiVu,^ 

Other authors have admitted a insertion of the ocular muscles as 

being able to bring about strabkmW generally, convergent strabismus 

Experiments made by wP 1 sky 4 and myself 5 in 1872, and recently 

1 Buffon observed thayffle^w^duction of strabismus is favored by opacities of the diop- 

trie media of one eye antVg^merally, by difference in the visual acuity and refraction of 
the two eyes. (Histvii^S'aturelle, Supplement, iii.) 

Stellwag has obwN^n films on the cornea in 22 per cent, of two hundred and eighteen 
patients affectedybA^nvergent strabismus, while of three hundred and fifteen hyperopic 
eyes without^eh^mi, 8.54 per cent, only manifested a deviation inward. 

2 Donc^^foiternational Congress of Ophthalmology, Paris, 1862; and The Anomalies 
of Accontonochation, etc., p. 297. 

^b^?^)lt, Refraction and Accommodation, translated by Culver, p. 116. 

v *Sfcobrowolsky, Klinische Monatsbliitter fur Augenheilkunde, 1872, ix. S. 473. 

Landolt, Annali di Ottulmologia, i., 1872. 



again by Botto, 1 agree with Donders’s. idea in this sense, that they show 
that the angle included between the macular axis and the papillary axis, the 
angle which I have called Epsilon (e), is usually greater in hyperopes than 
in myopes. If, as is probable, the papilla occupies a more constant place 
relatively to the insertion of the muscles than does the macula, these 
experiments would show that the macula is situated more temporally (out¬ 
ward) with hyperopes than with myopes. 

Instead of speaking merely of the angle alpha, or of the insertion of 
certain muscles, one could formulate the two apparently dissimilar theories 
in the following way. 2 Let the visual organ be considered as composed of 
two hollow spheres, one enclosed by the other. The inner constitutes the 
nervous coat, the retina; the outer represents the ocular globe properly 
so called, with the muscular funnel which envelops and moves it. We 
may call the latter the protective and motor coat. 

These two spheres are distinct from an anatomical as well as from a 
physiological point of view, and embryology shows that they are developed 
to a certain degree independently of each other. Hence it is permissible 
to assume that discord may be produced in the relative arrangement of the 
two systems. If, for instance, the retina has taken, relatively to the pro¬ 
tective and motor envelopes, such a position that the fovea centralis is placed 
somewhat outward , the visual lines will converge relatively to the axes of 
the ocular globes. This location of the fovea centralis, which is especially 
frequent among hyperopes, would necessarily favor the production of con¬ 
vergent strabismus. The opposite would take place if the retina had 
undergone in the course of its development such a rotationAs would have 
brought the fovea nearer to the nose. However, investj^mows concerning 
the place of the macula relatively to the muscular are still lacking. 

These considerations are, in fact, meant only to reGjiacile the two above- 
mentioned theories. .. 

There has also been brought forwarcL^gG^other accidental cause of 
strabismus, the length of the base-line. abnormal nearness of the 

centres of rotation of the two eyes, byJ^fcoring the action of the internal 
recti, ought to favor the production ofS*mvergent strabismus; an abnormal 
greatness of distance between the^a^lntres has been assumed to have the 
opposite effect. (Mannharck.^V^mas, who defends this theory, thinks 
that the progressive increa^sNvi the length of the base-line which results 
from the gradual devofepment of the ethmoidal sinuses may insensibly 
change the muscular eqmMirium to the profit of the external recti. 

One of the cirt^fijtances that have been accused not only of favoring 
convergent strabOms, but even of provoking it from the outset, is the 
excessive dcy£<s$H&knt of the internal recti relatively to the external recti . 

lnaTP^J (ft 

^Thirteenth Congress of the Italian Ophthalmological Society, Palermo, 1892 
(Ann (f 1ttalmologia). 

^^JL.andolt, International Congress of Ophthalmology, Heidelberg, 1888. 



Examination of the field of fixation has taught us 1 the fact, already 
pointed out by Donders, 2 that the temporal excursions of both eyes are al¬ 
most always restricted in convergent strabismus. This defect in motility, 
which is often not very pronounced in recent cases, is the rule for cases of 
long standing. It always is found in both eyes, often in the same degree. 
Frequently it is more developed in the deviating eye than in the fixing one. 
(Fig. 33.) 

Fig. 33. 

Fields of fixation of a person affected with a high degree of convergent concomitant strabismus of the 

left eye. 

Moreover, those who, like ourselves, are much given to the performance 
of muscular advancement have, during the operation, abimdant occasion 
to verify de visu the weakness of the external recti mi^fts in cases of 
convergent strabismus. These muscles are thin and especially in 

comparison with their powerful antagonists. 

If the weakness of the external recti, howeveXTs undeniable in con¬ 
vergent strabismus, we have to inquire whetha^Sjns primary or secondary. 
It seems to us that this defective devclo|fr?^h^of the abductors is due to 
a lack of use. Just as the internal nfrd^feecome strong by virtue of the 
constant exercise to which convergenqTVhbjects them, so the external recti 
remain or become weak, since the* only very imperfectly counterbalance 
their antagonists in convergenq0&fid since the associated lateral move¬ 
ments are neither very extq^i^nrn* well sustained. 


ice ourselves that in carrying our gaze from 
)ve our eyes much less than their excursions 

It is, indeed, easy to c 
one point to another /e 
would permit. If an object, instead of being situated just opposite to us, 


1 The fact, pm*Au>y Schneller and by myself, that the limitation of the field of fixation 
is met with in^^dyes, even although the strabismus seems to be localized to 6ne only, 
proves anev^^jWh reason there is for considering concomitant strabismus as binocular , 
due to an ^terktion of the convergence, and not as an anomaly in which only one eye is 
concern^fcASchneller, Archiv fur Ophthalmologie, 21, 1875, iii. S. 133; and 22, 1876, iv. 
S. ^4r\BaiTdolt, Archives d’Ophtalmologie, 1880-81, p. 586. 

^SjDonders, Anomalies, etc., p. 303. 



is somewhat to one side, or above or below the horizontal, we instinctively 
have recourse to movements of the head to direct our eyes towards it. 

I have experimentally determined the excursions which the eyes usually 
make before we change the direction of our face in order to carry our gaze 
from one object to another. These excursions do not exceed three or four 
degrees to the right or left; three degrees in elevation ; a little more, say five 
degrees, in lowering. 

From this it will be seen that the associated movements do not make 
any great demand on the ocular muscles. At all events, no demand is made 
at all comparable with that made on the internal recti in convergence. We 
may except the abductor of the fixing eye, which muscle counterbalances 
the internal rectus when it contracts under the convergence impulse. It 
is doubtless for this reason that the field of fixation of the eye which is 
considered the healthy one is often less limited at the temporal side than is 
that of the deviating eye. 

But when, in a case of very pronounced convergent strabismus, there is 
found a considerable limitation of the temporal excursion of the deviating 
eye only, without any change in the movements of the other eye, one has 
almost certainly to do with paresis of the external rectus, which paresis 
dates from the first days of life, and not with a concomitant strabismus. 1 

We have had occasion to mention a limitation of the field of fixation which is quite 
comparable to that found in strabismus; it is the one Huebscher 2 has discovered in torti¬ 
collis. The constant rotation of the head in such cases obliges the eyes to be constantly 
turned in the opposite direction ; then the excursions of both of them become limited, by 
lack of exercise, on the side towards which the face turns, in the sanA way that their 
temporal excursion diminishes in the case of convergent strabismus^^^^ 

Indeed, the local changes in an ocular miisclefaqpQcmtal weakness, 
vicious insertion, anatomical shortening (A. Graefi^Vspasm due to a kera¬ 
titis (Ruete), etc.), which many authors consicft^nie cause of convergent 
as well as of divergent strabismus, have not* been proved to be such, and 
their importance in the etiology of straijismils has certainly been greatly 
exaggerated. 3 Hansen-Grut has justly-wunonstrated that, even if they did 
exist, they would not produce the^\uWptoms which characterize genuine 
concomitant strabismus. 

It would be wrong, on f)i£JmKer hand, to deny the possibility of such 
malformations. Why slipS©- the ocular muscles be exempt from in¬ 
firmities which are mq^witn in all the other muscles of the human body? 
But it is certain that ra£y play only a very secondary part in the produc¬ 
tion of concomitanvSOabismus. It is for this reason that in our treatise 4 

1 LandoltJ^fltei^iational Congress of Ophthalmology, Heidelberg, 1888 ; and Landolt 
et Eperon, 1^^^, p. 892. 

2 Huebsc^Kr, Beitrage zur klinischen Cbirurgie, x., 1893, 2, S. 299. 

1890, p. 1; Gould, The Ophthalmic Record, p. 310, 1894. 

* tan dent et Eperon in de Wecker et Landolt, Traite complet d’opht., iii., 1887, p. 




we protest against the name muscular strabismus , which has at times been 
given to this form of ocular deviation. 

Hansen-Grut 1 develops the idea that the habit of a certain direction 
of the eyes may become the cause of strabismus. Thus it is that myopes, 
who, in accordance with Donders’s theory and daily observation, are pre¬ 
disposed to divergent strabismus, may exceptionally acquire a convergent 
strabismus. “Von Graefe,” says this author (page 25), “has rightly 
explained the cause of this form of squint to be the loss of power in re¬ 
laxing convergence induced by continuous convergence.” And he adds, 
“ In this case, therefore, it is the continuous habit . . . which ends by not 
being desisted from.” According to Von Graefe, Hansen-Grut, Berry, R. 
Cross and others, those persons who are constantly engaged with near 
objects succeed with difficulty in relaxing their internal recti muscles, even 
during distant vision. At the outset, it is held, this condition is accom¬ 
panied by homonymous diplopia; but this diplopia is said to be propor¬ 
tionately less troublesome as the eyes are less adapted to the vision of 
distant objects. Accordingly, it would not be the excessive myopes, who, 
as we shall soon see, can hardly furnish the convergence required by the 
nearness of their punctum remotum, but the medium myopes, who still 
enjoy good binocular vision, who should become the victims of this con¬ 
vergent strabismus due to habit. However, cases of this sort are very rare, 
and the ordinary form of strabismus of myopes is divergent strabismus. 

According to Hansen-Grut, it is likewise habit which converts the con¬ 
vergent strabismus of hyperopes, from being periodic, into a permanent one. 
It might be supposed, indeed, that, convergent strabisntffs^pf hyperopes 
being due to an excessive effort of accommodation wh&i^is # required for 
distinct vision, this strabismus ought to cease whea/N^p'accommodation is 
relaxed. This happens, but only at the beginnw^rf strabismus; later a 
part of the strabismus remains permanent, eve^Wjnring narcosis. Accord¬ 
ing to Hansen-Grut ( loc . cit., page 19), “ urtsN^Jbit, or, in other words, an 
unconscious innervation, which, owing*4(N64quent excessive convergence 
(effected in the interest of distinct visi/rv^ eventually brings about another 
functional position of rest than tha^vmch originally existed.” 

Donders said in 1864 (page/Nw'of his treatise on “Anomalies of Re¬ 
fraction and AccommodatioH^^jBoth the internal muscles of the eyes are 
therefore to be considered asSJ^ortened. The shortening, at first dynamical, 
as in the case of consul jktrabismus, becomes organic. It is the result of 
excessive action with*relaxation of the antagonistic muscles.” 

It is evident j^Pthe Dutch physiologist understood by “ shortening” 
of the muscles mi nuti on in length brought about by their contraction, 

and he cerfc$ifty> never doubted that this contraction took place under the 
influence o1\tanervation. Hence the difference between the explanation of 


JSnsen-Grut, The Bowman Lecture. Transactions of the Ophthalmological Society- 
United Kingdom, 1889-90, pp. 1-41. 

Vol. IY.—7 



permanent strabismus given by the above-named authors, on the one hand, 
and that given by Donders, on the other, is not very great. 

To express the matter simply, we would say : By contracting too much, 
the internal recti have become unable to relax entirely, or exaggerated 
convergence finally becomes habitual. Thus, on account of secondary ana¬ 
tomical changes, muscles which at the outset were normal become altered 
in their functions. 

According to Stilling, strabismus is due essentially to the position of 
equilibrium of the eyes; that is to say, to the position which the eyes 
assume when in a condition of absolute repose. The normal direction is 
obtained, according to this author, only by virtue of a constant contest 
against the power of inertia, which pushes the eyes towards their position 
of minimum innervation. Stilling has found, by means of a method 
of which we shall have more to say, that this position is rarely parallel¬ 
ism. Generally, the eyes abandoned to themselves diverge or converge. 
His investigations were made on intelligent persons capable of trust¬ 
worthy observation, students, doctors, and university professors, none of 
whom squinted. Now, we question if the result of these experiments jus¬ 
tifies the conclusion that it is the position of equilibrium that leads to stra¬ 
bismus. It seems to us rather to indicate that the position of equilibrium 
does not bring about strabismus, inasmuch as, in spite of the divergence 
of some and the convergence of others, no one among them had become 
strabotic. 1 

Moreover, nothing is more difficult than to determine the position of mini¬ 
mum innervation of the ocular muscles. Even, howevenfifi^we succeeded 
in determining for adults this position of equilibriuq^fef which so many 
authors lay special stress in connection with th<>©mesis of strabismus, 
would this determination be of very great qd^Tyteige ? We think not. 
This position of muscular equilibrium is fa»-<oom being an absolute, an 
independent, a primary matter. It is, tfnjhQ contrary, the consequence 
of the influence of a number of factors ^liuifrict upon the relative direction 
of the eyes. It is these diverse facto^jvhich, in the majority, conduce to 
the harmony of the movements ^ tne eyes, while they meet, in other 
persons, with obstacles which ii^peae the normal development of these 
movements, leave imperfec^oO) insufficiency, or occasion strabismus. Or 
is one to believe that the/’J&mtion of equilibrium that is found in a man 
twenty years old is tfoT mmo that he had when he came into the world, 
and which predisposed him either to the normal position of the eyes or to 
strabismus? position and the direction of the eyes not been 

^fcmed under the influence of the refraction (which, due 
be length of the globe, is much more constant than the 
of the eyes) and of the accommodation, the vision, the occu- 

formed and* 
essential 1, 
motor sysfi 



tilling, Archiv fur Augenheilkunde, xv., 1885. See also, among others,Wahlfors, 
Schielen, etc., Archiv fur Augenheilkunde, 1893, S. 207. 



pat ions, and by other circumstances of which we are yet ignorant, at least in 

All that the position of equilibrium can indicate to us is the relative 
direction which has become easiest to the eyes by virtue of these various 
influences,—a tendency to diverge or to converge; the direction in which 
an eye would probably deviate if binocular vision were to be lost. This 
position of equilibrium, however, is not the cause of strabismus; it can, at 
the very most, under certain circumstances, determine its character. 

Moreover, the fact brought out by Stilling, that in the immense 
majority of cases (“ in ueberwiegender Mehrzahl der Falle ”) hyperopes con¬ 
verge in a state of repose, while myopes in similar circumstances diverge , 
seems very significant. Emmetropes occupy the middle place between the 
two. This result is not at all astonishing. The relation between accom¬ 
modation and convergence foretold it. Such relations predispose hyperopes 
to converge, myopes, as we shall see, to diverge. 

It may be objected that it is not the position of equilibrium which the 
eyes present at the age when the Strassburg professor determined it, but 
that which they had at the beginning of life, which becomes the cause of 
strabismus. Were this so, his theory would accord with what we have 
said above concerning a want of harmony between the motor and the 
visual shells of the eyes. For the equilibrium in which the muscles main¬ 
tain the ocular globes has always reference to the direction of their visual 
lines,—that is to say, to the place occupied by the macula relatively to the 
motor apparatus. 

The inanity of the muscular theory of squint having 
ago, one hears it said upon different sides that it has^ 

new theory, the “central” or 


shown long 
replaced by a 
authors seem to 
believe that this theory differs entirely from that o^Donders. 

The words “ nervous” and “ central” have f X^vever, no significance in 
themselves. When Bonders showed that/flraS^planation of squint was to 
be found in the intimate relations of ^oi\ergence and accommodation to 
each other, when, before, with, and aftafX^m, clinical workers insisted upon 
the importance of binocular visic^in the etiology of squint, strabismus 
ceased to be considered a musculdKmection, and its causes were referred to 
the central nervous syste are to be found the connections between 

the innervation of convergen^tind that of accommodation, and where takes 
place the fusion of the ^wcTmacular impressions in the sensation of binocular 
vision. ~ 

Donders’s theftS^vhich we have exposed is, therefore, not only a so- 
called “ nervoq^!^ “ central” theory, but it has the great merit of explain¬ 
ing the variNQ^fiienomena that accompany strabismus, in conformity with 
daily obse^^tion. 

Smj^Donders’s day much progress has been made in our knowledge 
of^dnNanatomy and physiology of the brain, and one may now express 



Oh ew language certain things that had by no means escaped the notice 



of earlier observers, but which they expressed in terms different from those 
which we actually use. Thus, for the term “ binocular vision/’ M. Pari- 
naud 1 proposes that of “ macular reflex of convergence/’ this reflex being 
comparable to the accommodative reflex of convergence, etc. 

In the light of more recent cerebral physiology, the etiology of squint 
will no doubt become clearer. What must not be lost sight of, however, 
is that the origin of squint is, nevertheless, as before, attributed to the rela¬ 
tions between accommodation and convergence and to the alterations of 
binocular vision. The attempts that are made, reasonably enough, to pro¬ 
gress towards a more exact localization of the causes of strabismus in the 
central organ do not mean that from this date it has to be considered as a 
properly so-called cerebral affection. Changes in the centres of innerva¬ 
tion as primary causes of strabismus are admissible only in certain defi¬ 
nite cases, and are accompanied by other characteristic symptoms. It is 
found, for instance, as the consequence of neoplasms, tabes, insular scle¬ 
rosis, hysteria, neurasthenia, syphilis, morbus Basedowii, chronic alcohol¬ 
ism, etc. Here we are not dealing with strabismus due to lesions of the 
brain or nervous system. To do so would be to encroach on the domain 
of our colleagues, Standish, Stevens, and Swanzy, to whom has been assigned 
the interesting subject of the relations between the visual organ and central 
affections. 2 

Essential paralysis of divergence , which causes convergent strabismus, 
is often betokened by homonymous diplopia, which persists without notable 
modification in whatever direction the patient may look. 3 It may even be 
combined with a defect of convergence 4 5 and with paratad(sc^* some isolated 

muscles of the eyes. . . . J2T 

Convergent strabismus may be due also to a^QSm of convergence , in¬ 
dependently of accommodation and refraction r e have observed cases 
of this kind in hysteria. 6 It is perfectly admissible that the same phe¬ 
nomenon is produced in consequence of^omeC irritations of the centre of 

To conclude, however, that all s(njmsmus has a similar cause seems to 

1 Annales cPOculistique, 1896, pi 

2 Consult on this' subject GeflffiW Stevens, Oculo-Museular Defects and Nervous 

Troubles, 1880; Oculo-NeuralN^$(?x Irritation, International Medical Congress, 1889; 
an essay presented to Academy of Medicine, Brussels, 1884; Parinaud, Para¬ 

lyses des Mouvements *fcocl§s des Yeux, Archives de Neurologie, 1882; Noyes On the 
Tests for Muscular Asihenopia and on Insufficiency of the External Recti Muscles, Trans¬ 
actions of the Eight^Kernational Medical Congress, Copenhagen, 1884; Diseases of the 
Eye, p. 200 ; Lanflojt et Eperon, loco citato, p. 922. 

3 Parinatffijvofeo citato. 

4 La^l^^VEperon, loco citato, p. 902. 

5 ParinVhl, Gazette hebdomadaire, 1879, and Compte-rendu de la Societe d’Ophthal- 
mologjs^fcaris, 1889. 

among others, Borel, Arch. d’Opht., 1886 and 1887, January, July, August, 
^stero-traumatismes oculaires, Congress at Rome, 1894 ; de Lapersonne, Recueil d’Oph- 



us to go too far; and to declare that convergent strabismus is due to an 
excess of energy of the centre for convergence, and vice versa for divergent 
strabismus, is arguing too simply. If one squints towards the nose, without 
being the victim of paralysis of the abductors, it is because his adductors are 
not held in equilibrium by the abductors,—because the former contract too 
much, the latter too little; and since the muscles contract only under the 
influence of a nervous impulse, it is evident that in this case there must be 
an absolute or relative excess of the innervation for convergence. Hence 
this way of explaining strabismus is in reality only a circumlocution. We 
would like to know whyt\\e centre of convergence shows itself so exuberant 
in convergent strabismus, and why in divergent strabismus this centre fails 
to do its duty. 

Donders has first answered this question in a way which is satisfactory 
for the immense majority of cases of strabismus. He has given an expla¬ 
nation of its principal forms, in demonstrating the influence exercised by 
accommodation, and binocular vision upon the direction of the eyes. 1 

The commonest form of convergent strabismus, that which accom¬ 
panies hyperopia, dates most often from the first years of life. 

The occasional cause of the development of deviation often remains 
obscure. It not infrequently appears after a prolonged exclusion of one 
eye, as by a bandage used for keratitis e.g. In this case, it is evidently 
the suppression of binocular vision which allows the hyperopic child to 
facilitate his accommodation by an excess of convergence without being 
troubled by diplopia. The efforts of near fixation are especially favorable 
to the development of convergent strabismus. This forn^n%uint usually 
appears at the time when the child begins to fix his atteJUtfton upon objects 
which are shown to him, especially those close at liaaQ^which it can seize, 
or later, when the study of the alphabet commer impose its exigencies 

upon vision. It affects especially young cldrahen of puny constitution 
who have weak accommodation. A certain nwnber of them discover ac¬ 
cidentally the artifice of procuring grd&^er distinctness of vision by the 
sacrifice of one eye. The exaggerated^^pulse of convergence is then en¬ 
tirely of a reflex nature, as are the ^vements of our eyes which follow the 
displacements of our attention jjjQkice. Some hyperopic children, on the 
contrary, as Mauthner point^ od^ learn from their comrades, by imitation, 
the art of squinting. They Squint at first at will, then involuntarily, if 
not unconsciously. Scijwftgger cites, conversely, an instance of a young 
boy who voluntarilwQu red himself of convergent strabismus, and I have 
published ( Arch . ftimpht., xvi. p. 404) the case of a young woman who 
noticed, whik liking at herself in a mirror, that when she saw distinctly 
with one eroN^e other was turned inward. She thus practised squinting 
or not sqmiming at will. In the latter case her vision was, of course, 



0 1 Landolt, L’Etiologie du Strabisme, Arch. d’Opht., 1897, p. 74. 


if, as is sometimes the case, the strabismus has developed under the 
influence of convulsions, we may infer that alterations in the nervous 
centres have contributed to its production. 

Hyperopic convergent strabismus generally commences by being periodic 
or alternating . It is oftenest, at the outset, also relative. From a very 
early stage binocular vision has ordinarily undergone profound but still 
reparable injury. Later the strabismus becomes permanent , absolute , and 
localizes itself in one eye, generally in the weaker, though it may remain 
alternating for years. When it tends to spontaneous cure, it traverses the 
same stage in the opposite sense; after having been permanent, it resumes 
its periodicity or relativity, and sometimes may disappear entirely. But, 
although in such cases the deviation is effaced, complete binocular vision 
is not always spontaneously re-established. 


The principles of the treatment of convergent strabismus are the logical 
outcome of what we have just shown concerning its etiology. 

The excess of convergence which constitutes this infirmity being in the 
immense majority of cases due to a defect of refraction which necessitates 
an exaggerated effort of accommodation, one will try, in the first place, to 
remedy this defect, whether due to hyperopia or weakness of accommoda¬ 
tion, by means of convex glasses. 2 

If the spasm of convergence shows itself too tenacious, one must have 
recourse to the complete suppression of this function by mteans of mydri - 
atics. 3 The accommodation being excluded, convergen$^syleprived of a 
very important stimulus. jzr 

Moreover, as the production of strabismus is by the inferiority 

of one eye, we must correct the optical errors o£^iaaeviated eye, especially 
astigmatism, and restore its visual power by ^y^ising it. 

Still more important than the trainin^)flmie eye by itself are the exer¬ 
cises which bring into action both eye^^imultaneously for the purpose of 
stimulating or re-establishing binocula^^sion. 

The principal cause of strabkfifjjs and the greatest obstacle to its cure 
being the absence of binocularQteion, it is evident that anything which 
tends to re-establish the fusion of the retinal impressions of the two eyes 
constitutes a valuable tte^araeutic agent in the treatment of this infirmity. 

Finally, if these m^a^s, which we shall call pacific , are inadequate, we 
may resort to opera^^c interference. 

These are tl/S^emedies at our disposal with which to combat conver¬ 
gent strabism^>Let us see now how they may best be used. 

It is ^viMht that, if we are dealing with a very young and frolicsome 
child, wig shall not think of making him wear glasses to cure the hyperopia 

K^mpare Landolt, Refraction and Accommodation, translated by Culver, p 399. 

Donders, Anomalies, p. 305. 

er 3 John Green, Transactions of the American Ophthalmological Society, 1870, p. 138. 



which the ophthalmoscope has revealed. We content ourselves in such 
cases with the use of mydriatics, taking pains to advise the parents to pre¬ 
vent the child, as much as possible, from looking at small objects near by. 
Nothing is lost in such cases by deferring energetic treatment. The muscu¬ 
lar conditions, the relations between convergence and accommodation, etc., 
are much modified, and often very advantageously, as the child’s develop¬ 
ment proceeds. 

The spontaneous cures, also, of convergent strabismus 1 moderate the 
medical, and still more the surgical, impatience of the specialist. 2 

If the strabismus affects children of more advanced age, but is still only 
at its commencement ,—that is to say, if the exaggeration of convergence has 
not yet become permanent, and arises only under the influence of a tran¬ 
sient act of fixation,—in such cases resting the eyes , the cessation of all work 
necessitating an excessive effort of accommodation, will sometimes suffice to 
dispel the deviation which otherwise would become persistent. 

Nevertheless, in order not to condemn the child to absolute inactivity, 
especially if it has already begun its studies, we shall relieve the accommo¬ 
dation of at least a part of its work by means of convex glasses. Thus it 
may be that wearing glasses which correct the manifest hyperopia prevents 
the deviation in young hyperopes, or suffices to cure it when it has just 

It is clear that if hyperopia is accompanied by astigmatism, the latter 
should be corrected at the same time. In this way the ciliary muscle will 
be doubly relieved,—first, by being spared the correction o£^a part of the 
optical defect; and again, because the patient is thus ej^^ec? to hold his 
work at a greater distance, thanks to the increase oio&l visual acuteness 
afforded by the cylindrical glasses. It is best, ind|^p, in all cases of con¬ 
vergent strabismus to advise the patients to ho^^e objects of fixation as 
far away as possible. 

According as strabismus is more or ks^Jacious, one will prescribe the 
glasses to be worn constantly or only f^lSysion near at hand. 

If the strabismus has becom e-nemanent, even the constant use of 
glasses which correct the manifesfcJj^peropia will not suffice to dispel the 
deviation. One would natim^^® led to think, in such a case, of ex¬ 
cluding even a greater am^t of accommodation by correcting the total 
hyperopia. Such a coitfffhSitfi would be perfectly logical. But if, for such 
a patient, we simply prescribe glasses correcting his total hyperopia, we 
shall never obtain^Mj)desired effect, and that for the simple reason that 
the patient is nc )t @e to relax his accommodation sufficiently. In order to 
achieve our^d^^t we must, therefore, have recourse to mydriatics. 

Indeed^^^oon as we have to deal with a young hyperope whose stra¬ 
bismus become permanent, we subject him, first of all, to a course of 


lAonWecker, Klin. Monatsbl., p. 453, 1871; Schneller, Arch. f. Ophth , xxviii. 3, p. 

IV " 2 Landolt, International Congress of Ophthalmology, Heidelberg, 1888. 


treatment with atropine. We instil into both eyes once or twice daily, 
according to the age of the patient, one drop of a solution of the drug 
(1 :400, or 1 : 200). It is advisable to keep the eyes closed for five minutes 
after the instillation, in order to increase the effect of the mydriatic and to 
prevent poisoning. If the age of the patient permits, we immediately give 
him glasses which correct the total hyperopia. In anisometropia each eye 
will, therefore, be fitted with its correcting lens. For protection against 
bright light we select smoked and large glasses. 

Very young children, for whom the wearing of glasses is impracticable, 
must be protected from the dazzling light by a veil or shade. In no case 
do we allow the patient, at the beginning of the treatment, to use his eyes 
for looking at near objects. We try, indeed, to avoid convergence not only 
by forbidding the patient to make any attempt at near vision, but also by 
taking away distinct vision for near objects, and consequently, as much as 
possible, the inducement to near vision. 

If, after a few weeks’ properly continued treatment, it appears that, 
with the required glasses, neither the strabismus for distance nor that for 
near vision returns, we may order for children of studious habits spectacles 

to be used while working; but we must at the same time emphatically 
advise them not to abuse our permission to return to work, and to take it 
up at first for but a few hours each day, and with frequent intermissions. 

Thus it is often possible to continue a course of atropine treatment for 
months without serious detriment to the child’s studies. By and by we 
may try to diminish the dose of the mydriatic, or even^kXdiscontinue it 
altogether. If this succeeds without the patient relapsing into 

squint, we change the glasses which have hitherW^en worn, for the 
strongest convex lenses with which he is ableJ^^e at a distance. In 
anisometropia and astigmatism we follow thej^S^r given elsewhere. 1 The 
patient must now wear these correcting gkffiSfOonstantly; but he no longer 
requires special glasses for working, as Via/accommodation has again at¬ 
tained its full power. pN 

The strabismus is, in fact, ciu^o^and we may congratulate ourselves 
upon the result obtained, in s^Pof the necessity of wearing working 
glasses. If, after some tii^^^^expired, there has been no recurrence of 
strabismus, we lessen theJsMngth of the convex glasses and endeavor to do 
without them, at ffr^fp^seeing at a distance, later at work. In favor¬ 
able cases we succe£(Nmus in dispensing, little by little, with the use of 
spectacles. Thi|>fe2he case especially when the hyperopia is of moderate 
degree, the scumjbut slight, the visual acuteness good in both eyes, and 
the constftA^n robust. Such cases, which are not very rare, constitute 
real triumphs of the healing art. 

GjAter difficulties have to be surmounted in the treatment of conver- 
in^rabismus where the visual acuteness of one eye is very slight. As 


Landolt, Refraction and Accommodation, translated by Culver, p. 526. 



has been said, and as can be readily understood, it is always the more de¬ 
fective eye which deviates. Besides the course of treatment above indi¬ 
cated, we seek in such cases to restore the weak and deviating eye to the 
accomplishment of its normal functions. Therefore, errors of refraction 
will need to be most carefully corrected, and we must seek to augment 
its visual power by special training. Such training must, however, always 
be undergone while the accommodation of both eyes is excluded, and must, 
moreover, never be continued until fatigue sets in; otherwise we incur the 
risk of increasing the strabismus. The squint naturally manifests itself in 
the healthy eye as long as the weak one fixes. This is the reason why in 
such cases we always add to the training of each eye by itself stereoscopic 
exercises involving the simultaneous use of both eyes. 

In this way may be achieved an infinitely more important result than 
the improvement of the visual acuity of the deviating eye,—namely, the 
re-establishment and consolidation of binocular vision , our most powerful 
aid in every therapeutic attempt to combat strabismus. 

Although Dubois-Reymond had already foreseen the service that the 
stereoscope might render in the cure of strabismus, it is to Javal 1 that we 
owe the principles and the development of its use in ophthalmology. 

The principle of the stereoscope exercise is to present to the eyes two 
images, differing from each other in such a way that, by their fusion into 
one, the impression of a solid, of perspective, of the third dimension, may 

To begin with, two vertical lines may be used, one qfctove, the other 
below the horizontal, which, seen stereoscopically, beco^fcw single line. 

(Fig. 41 .) oy 

In order to facilitate the fusion of the stereosc^Mv^uimages they should 
have some parts in common. If the images <ai^)etters, the words which 
they compose thus become complete only fusion of the two parts. 

Those marks are likewise to be found Cn very practical stereoscopic 
figures devised by Dr. Fromont, 2 chi^f^urgeon of the Belgian army, in 
those of Dr. Dahlfeld, and in the moi^^ecent ones of Dr. Javal. 

In our Fig. 34 the central pohj^vhich is common to the two drawings 
will guide the patient’s eyes. A^Aer mark is formed by the striped square, 
in which, in the figure on fli^krt, the central circle is lacking, while it is 
found on the right, wlm’d^ie rest of the square is empty. The fusion of 
the two slightly dissitl^l^ figures of a truncated pyramid will give to the 
individual a vivid s0*ption of perspective. 

We always care, when requiring a patient to look at stereoscopic 
figures, to ftir^ijHi each one of them with points which alone can surely 
tell us if thivpatient is taking account of the perspective solely by the 
aspect tme picture itself or by stereoscopic fusion of the two. Thus, 


^ i 

al, Ann. d’Oc., lxv. pp. 197, 971; lvi. pp. 5, 113, 209. 
une, xvi. p. 303, v. Manuel du Strabisme, 1896. 

International Congress of the Medical Sciences, Brussels, 1875. 

Bulletin de l’Acad. de 



it will be noticed in Fig. 35, which represents an avenue in the park at 
Versailles, that in the left picture the statue on the right of the foreground 
bears a black spot, while in the right picture it is the statue on the left 
which bears the black spot. In the fusion picture both statues ought, 
necessarily, to be marked. If the patient says that he sees only one which 
is marked, and tells which one it is, we know at once that he is using but 

Fig. 36. 

one eye, and we know which eye he employs. There may be noticed also 
the spot on the reflection of the right statue in the right figure. This 
enables us to ask the patient whether or not the reflectioipjfom the water 
are like the corresponding statues. At times we also^gs Avo points on 
one side and one point on the other, as in the sk^^Rg. 35. We place 

Fig. 37. 

neatstone’s mirror-stereoscope. 

them so that in ri^^ision picture the three points will be on the same line, 
one between thd^ners. 

By the^^yf these marks an attentive patient may exercise quite by 
f,Sraipliing as to whether he sees monocularly or binocularly. 1 




sgards the photographic views which one finds in commerce, it is to he noticed 
q corresponding points of the two pictures are much farther apart than are the 
Hence one nearly always needs to have recourse to adducting prisms to facilitate 
yjjf]sif>n : or to cut off a piece of each, in order to use them in our stereoscope without prisms. 

Corresponding points on fusion pictures. 

— - — 


The most useful pictures are those which, like Wheatstone’s (Fig. 36), 
procure, for the person who sees them binocularly, the impression of a solid. 

Javal’s stereoscope with five movements. Holmes’s stereoscope. 

Any stereoscope may be used for these exercises. Javal formerly used 
Wheatstone’s stereoscope with mirrors (Fig. 37). Since then he has per- 

Fio. 40. 

fected hh 

Oliver’s stereoscope. 

by the five movements’ stereoscope (Fig. 38). This 

instmfl^^; may be regarded as a derivative from the well-known stereo- 

scfoe of Holmes (Fig. 39), the Mexican or American stereoscope, 
eptible of more varied applications than the latter. 

It is 


Another stereoscope very useful for our purpose is that devised by 
Oliver (Fig. 40). It is susceptible of eleven different forms of adjust¬ 

We employ for the re-establishment of binocular vision a very simple 
apparatus 1 (Fig. 41). It consists of an ordinary stereoscope box, from 
which we have removed the prisms, in order to substitute for them what¬ 
ever glasses from the trial-case may be desirable, whether spheric, cylindric, 
prismatic, or a combination of them. 

Fig. 41. 

Landolt’s stereoscope. 

The upper part of the figure represents the stereoscope b^T^Miished with glasses which adapt 
each of the two eyes to the distance of the visual objects. 

These latter are fixed to two boards which slide one \noJ the other in such a way that one can 
alter at will the distance between the two figures. T^As distance is indicated in millimetres by the 
division of one of the boards. 

The figures to be fused are represented here by maJsimple red lines, the one corresponding to the 
point zero, the other to the sixth centimetre of tj^Jivision. 

It is well to make the partiJ^W^f the stereoscope rather long, in order 
to prevent one eye from tre^2§uig on the visual field of the other. The 
visual objects placed aV^tmJbpposite end of the box from the eyes to be 
exercised may be brougkfeJnearer to or separated from each other at will. 
They may even be*^»j^d one above the other, or inclined relatively to each 
other. Q 

The prin^i,m .9 t)f an 7 stereoscope useful for the treatment of strabismus 
is that th^Aj^trument employed places the eyes in the conditions which are 
most favfkaole to the fusion of their retinal images . 

^ -- 

andolt. article Strabisme, in Diet. Encyclopedique des Sciences Medicales, Paris, 
and Refraction and Accommodation of the Eye, translated by Culver, p. 408. 



One of the eyes being generally weaker, or in any case less exercised, 
than the other, it is a question, first of all, of making its visual impres¬ 
sions as vivid as possible. For that purpose we correct its astigmatism and 
adapt it with perfect precision to the distance of the object which it is to 
see, in order to procure for it an absolutely clear retinal image. After 
doing so, we must seek the relative position of the two figures in which 
their fusion is possible. 

Let us take, for example, our stereoscope and place the test objects at a 
distance from each other approximately equal to that between the two eyes. 
Under such circumstances their fusion into one single impression necessi¬ 
tates the parallel direction of the eyes. Knowing that this parallelism is 
generally possible only in the absence of any accommodative impulse, we 
provide the patient’s eyes, or the sight-holes of our stereoscope, with glasses 
which permit him to see at the distance of the objects without any effort of 

Ordinary stereoscopes being generally about 166 millimetres (|- metre) 
deep, emmetropic eyes would require convex 6 D. to fulfil this condition. 
If we have to do with a hyperope of 4D., we shall give him convex 10 
(4 D. to correct his hyperopia and 6 D. more to adapt him for 166 milli¬ 

It will be noticed, however, that, even under such circumstances, the 
majority of patients do not succeed in fusing the images. This may be 
due merely to incapacity to direct their eyes parallelly. We then help the 
patient to find the distance between the objects which is requisite for the 
fusion of their images. When he has succeeded in dok&>tl«is, we shall 
gradually separate the objects more and more until is effected with 

perfect parallelism, or even slight divergence of the Tii^ of fixation. 

But the greater part of the time the patients^Qot fuse, whatever may 
be the interval between the two objects. Th(^js6e alternately the one or 
the other, when the vision of the one eye^s\obut as good as that of the 
other, or only the object corresponding tl&ihe better eye when the vision of 
the two eyes is different. 

In this case it becomes a qn of attracting the attention of the 

weaker eye to the object whieKlcOTesponds to it, to cause it to fix ener¬ 
getically, excluding its cong^ACJ By successively covering and uncovering 
the better eye for longer >rter intervals,—indeed, even by furnishing it 
with a too strong convlxjjiass which lessens the clearness of its vision,—one 
may succeed in caugj5^ the patient to see the two objects simultaneously, 
and at length to/fiNeihem into a single one. Much patience is required, 
in order to aojffwe this result, on the part of the surgeon as well as of 
the patie^iN ; If is for this reason that this training, so logical and use¬ 
ful, is far rrom having found in ophthalmic practice the place which it 

AThere exists, indeed, an infinity of forms—sometimes very strange ones 
—of incapacity of fusion. There are persons, for instance, who succeed 


in seeing double,—that is to say, in perceiving simultaneously the visual 
impression of the two eyes. It might be supposed that nothing could be 
easier than, by means of prisms or of the stereoscope, to cause the retinal 
images to fall simultaneously on the fovea centralis of each eye, and thus to 
obtain the fusion of the two. This is, however, often impossible. Just as 
in those cases homonymous diplopia changes suddenly into crossed diplopia 
as soon as the double images have been brought very near each other, simi¬ 
larly in the stereoscope the images change sides rather than become fused. 
It is for such cases that Javal has devised as test object for one of the eyes 
a wafer surmounted by a black point, while that for the other eye is a series 
of such wafers, so placed that the fusion of the former with one of the latter 
becomes almost inevitable. The little point serves as a mark by which to 
know if fusion has taken place, and with what amount of separation of 
the test objects. But such is the alteration of binocular vision in some 
cases, that even this experiment, which would seem to be absolutely conclu- 

(the wafer), and only perceives that of the little point which is formed on 
an eccentric part of its retina. 

When the patient is able to see simultaneously both the images in the 
stereoscope, this is certainly already a satisfactory result. The goal, how- 

considered attained until the patient is fully conscious of the third dimen- 

the re-establishment of binocular vision, we may cite the results 
limn we have obtained by means of stereoscopic training, even in cases 
lierein surgical intervention only was able to overcome the ocular devia- 



tion. 1 Since our original communications on 'this subject, cases in which 
binocular vision has been restored after strabotomy, in spite of great differ¬ 
ences between the two eyes, have considerably increased in number. Nor 
would we ever give up these attempts at the restoration of binocular vision, 
since they help to complete and to consolidate the cure of strabismus. 

For emmetropes or myopes who are still young , and who are affected by 
convergent strabismus, it is best to employ the same curative means as in 
the case of hyperopes,—that is to say, repose of the eyes, abstinence from 
near work, atropinization, and stereoscopic training. Rest and complete 
paralysis of the accommodation have, indeed, for all eyes a relaxing influ¬ 
ence on convergence. 

After having thus obtained the disappearance of the strabismus for 
distant vision, we make emmetropes and persons who are slightly myopic 
wear convex glasses strong enough to exclude all effort of accommoda¬ 
tion during near vision. By gradually diminishing the strength of these 
glasses, we sometimes succeed in accustoming the patients to accommo¬ 
date sufficiently without augmenting unduly their convergence. Strabis¬ 
mus thus cured for near vision will be all the more surely cured for distant 

Stereoscopic training, carried on at the same time with the use of 
mydriatics, according to the principles above explained, is more than ever 
indicated in such cases. 

But if. the convergent, concomitant strabismus of non-hyperopes is met 
Avith at an age when mydriatics can hardly modify the relations between 
com r ergence and accommodation, or under conditions Avlm^ra^ke illusory 
the effect of orthoptic treatment, it must be corrected sui^mally. 

When com r ergent strabismus is due to a spasm of/h^-convergence other 
than that provoked by accommodation, the Aveawkmg of the poAver of 
divergence is almost always a symptom of a&irfrection of the nervous 
system. Hence it is this latter which combated first of all by 

means of a rational general treatment. cJuKfmdition, this form of strabis¬ 
mus may be treated directly and accctfCfciVg to the same principles which 
Ave have explained Avhen speaking of ordinary convergent strabismus. 
Even atropine can sometimes rerf&S^service, still more orthoptic exercise, 

y open 


alone at first, and then aidedO^Sp 


time, ordi 

one has a to proceed to the operation for strabismus, 

Tent of cona^ergent strabismus. 


If, after a certtpigtime, ordinary treatment shows itself to be ineffica- 

k to 

1 Landol^^S^^tional Congress of Medical Sciences, Washington, 1887; American 

Journal of O^fchalmology, p. 264; Arch. d’Opht., vii. p. 409; British Medical Journal, 
ii. p. 844^887; Arch. d’Oplit., viii. p. 34; France Medicale, 49, 1888; Internat. Ophth. 
Cong^sNf^idelberg, 1888; Yialet, De la Cure du Strabisme dans ses Rapports avec 
l’x^mt^visuelle de l’ceil devie; Arch. d’Opht., 289, 1890; British Medical Association 
ng in Carlisle, 1896. 




This “ certain time” during which ordinary treatment ought to continue 
will necessarily vary according to a great many circumstances. One ought 
not to think of surgical intervention as long as an attentive examination 
shows a diminution in the angle of strabismus. Even if the latter remains 
stationary, but without exceeding a few degrees, one could still defer the 
operation, if the youth of the patient gave a right to hope for an ulterior 
development of his constitution, and if the good condition of the sight of 
both his eyes entitled us to count upon the powerful aid which comes from 
binocular vision. 

It is quite another thing when the strabismus dates from long ago, 
when mydriatics do not modify it, and when it is concerned with a very 
amblyopic eye. In such cases one can proceed to operate without hesi¬ 

What shall this operation be? The great majority of oculists will 
still answer this question as it would have been answered a century ago : 
“ It is best to do a tenotomy , or two, or three, or, if necessary, a reinforced 
tenotomy of one or both of the internal recti.” 1 

Our opinion differs considerably from this routine. Since muscular 
setting back has been practised for the correction of convergence, experi¬ 
ence has proved that, although the immediate effect of this operation is 
frequently insufficient, its final result is very often excessive. Even for 
the correction of convergent strabismus of twenty degrees a considerable 
setting back is required, one which is obtained oftenest only by means of 
sutures pulling the eye forcibly in the direction opposite! to the tenoto- 
mized muscle. Or it is necessary in such a case to s^t^aek the internal 
recti on both eyes. Now, convergent strabismus of tK&^egree is certainly 
not an extraordinary one, since it may amount to fi^vfegrees. 

If the correction of the strabismus is not^c^mplete, the parents of the 
young patient are not satisfied, and say that rfmmuld “ still squints.” This 
objection, by itself, constitutes only a mod^rata inconvenience ; but the young 
patient who to-day squints a little i?&anfwill squint outward in a very 
troublesome way next year, or soon 0je1 hvards. And this divergent stra¬ 
bismus which the surgeon has ^jisioned by weakening of the adductor 
muscles will increase in prop(0jySn as the age of the patient advances. 
Only slightly disfigured l^^^the operation, he will be hideous later, espe¬ 
cially since the divergenpyr the eye brings still more into notice the part 
of the globe which frasjBeen deprived of its muscle, and the hollow due 
to the retraction^ o^the caruncle. A graver consequence of this divergent 
strabismus is sjampTmes the crossed diplopia which torments the patient, 
provided a^stfi^worse thing does not happen,—namely, that his binocular 
vision be^jm£k and remains entirely abolished. 

Ew3iN^hen the tenotomy of the adductors is not followed by divergent 
strabfeqaus, there almost always remains a weakness of that important func- 

All these facts are readily explained. We know, in the first place, that 


convergent strabismus is almost always due to a spasm of the adductors, 
which spasm tends to diminish as age advances. Now, if by setting them 
back one weakens these muscles to the extent that, in spite of their con¬ 
traction, the eyes have only just a parallel direction when looking at a dis¬ 
tance, this parallelism will be changed into divergence in proportion as the 
spasm diminishes. Divergence being once established, the individual will 
instinctively hasten to renounce binocular vision. Only on this condition 
can he escape diplopia. His amplitude of convergence has, indeed, under¬ 
gone a considerable reduction by the tenotomy of the muscles that bring 
about convergence; so that, even with the most fatiguing effort., the patient 
can keep lip his convergence only for a limited time. 

All these dangers are avoided if, instead of weakening the adductor 
muscles by setting them back, we increase the strength of the abductors by 
advancing them. 1 This method is especially indicated since, as we have 
demonstrated, the external recti muscles are almost always weakened in 
convergent strabismus. 

The favor enjoyed by tenotomy in the estimation of so great a number 
of our colleagues is due, in the first place, to the facility of its execution, 
and then to that theory, as erroneous as it is inveterate, according to which 
the antagonist gains in power that which the tenotomized muscle loses. 

Krenchel 2 has demonstrated theoretically the falsity of this theory; 
practice demonstrates it still more clearly; one has only to examine care¬ 
fully the excursions of the eyes before and after strabotomies. 

We may graphically represent the effect of tenotomy and that of mus¬ 
cular advancement in the following way : 3 

Let Fig. 42 be a left eye 4 affected with a convergent stSytemus of thirty 
degrees. Let M be the centre of rotation ; FS, the iSi^Kdi recti on of the 
line of sight; MN , the normal direction ; E , the^J^rnal rectus muscle, 
with its insertion at e; i, the internal rectus, wj&^fre insertion at i. 

If we would desire to give to this ey^fts^Jbrmal direction by means 
only of the setting back of the internal rb&ws, 
disengage this muscle considerably fro^Y^s attachments; indeed, even to 
cause the globe to turn by force to tkptemporal side. On account of this 
rotation, the internal rectus wouI&Xnid itself strongly drawn back from 

ui be still more strongly drawn back; 

Wis i 

the edge of the cornea. Bu< 
for, detached from the glota^ 

muscle will not fail to retract, according 

1878; Refraction and Accommodation, translated 
al Congress of Medical Sciences, Washington, 1887 ; Inter- 


1 Landolt, report of nis TTlnic, 
by Culver, 1886; Inte*^£ 

national Ophthalmolith Congress, Heidelberg, 1888; Edinburgh, 1894; Arch. d’Opht., 
1894; No. 3, 18£>5i$mish Medical Association, Carlisle, 1896. 

2 KrencM%i|^h. f. Ophth., xix. ii. p. 275, 1873. 

3 See oui\^)ort, already cited, to the International Congress of Ophthalmology, 

Ileidelbei^Vl 888. 

4 *1^^diagram has been made as correctly as possible. The data have been obtained 
froii^eihonal investigations on the cadaver, and from the anatomical drawings of Arlt and 

KJ Vol. IY.-8 


to its contractility and to the degree to which it has been disengaged from 
its attachments. 

This latter factor—the retraction of the tenotomized but none the less 

innervated muscle—seems to have 
been overlooked by many operators, 
who took into consideration only the 
rotation given to the eye by the ex¬ 
ternal rectus deprived of its antago¬ 

And this is not all; they have 
fallen into another grave error. In 
the belief that the centre of rotation 
of the eye is a fixed point, they have 
imagined that an eye deprived of the 
influence of its internal rectus can 
but rotate towards the temple round 
this centre. But the centre of rota¬ 
tion is not a fixed point in space. 
It results from the combination of 
all the forces which influence the 
position, the direction, and the rota¬ 
tion of the eyeball. * 1 Among these 
forces are some which, as the four 
recti muscles, draw^Ae eye into the 
back of the oibit; others, on the contrary, which tendWV advance it, such 
as the oblique muscles and the orbital diaphragr *hen one of these 
forces is removed, the others come more into proirir^ehce and the centre of 
rotation is changed. Paralysis of one of the^fc^r muscles is sufficient to 
cause a certain amount of exophthalmos. MVmg enucleation the eye falls 
forward gradually as the recti muscles jfreYuffe. The protrusion of an eye 
in consequence of a perfect tenotomy >L>es not escape the notice of an ordi¬ 
nary observer, for it produces marldj^msfiguration. Now, this protrusion 
is a third reason why the tenohj^zed muscle is carried back behind its 
normal insertion, which mu^ClJken its power over the eyeball and limit 
the excursion in that dire^|w 

Does the rotation opposite direction in any case increase by the 

setting back? Thi^sJar from certain ; it may even decrease. 

To begin wjtjg^if we find the temporal excursion of the eye limited in 
a case of convp^nt strabismus of long standing, this limitation is due not 
so much to 4^^ntraction of the internal rectus as to the weakness of the 
externajS^^is consequent on want of exercise. It does not exist, indeed, 
at theioufcset of the strabismus. 

Left eye. Convergent strabismus of 30°. 

A i Landolt, Report of the International Ophthalmological Congress, Heidelberg, 1888; 

1 Jritisl 

British Medical Association meeting, Carlisle, 1896; Arch, of Ophth., 1897. 



The injury done to the internal rectus by its setting back does not 
directly benefit the external rectus. On the contrary, the falling forward of 
the ocular globe that follows the setting back of a rectus muscle has an 
equally unfavorable effect upon the action of the external rectus. The 
advantage for the excursion on the side opposite a tenotomy is, therefore, 
generally not very marked. It may, indeed, be nil , or even a negative 

Suppose that, under the influence of the three factors, the contraction 
of its antagonist, its own more powerful contraction, and the propulsion of 
the eyeball, the insertion of the te- 
notomized muscle is carried from i to 
i' (Fig. 43), the line ei represents the 
limit of the muscular funnel in the 
horizontal meridian before the tenot¬ 
omy, ei' the limit after the tenotomy, 
and iei' the amount of the protrusion 
of the eye, freed from the lateral mus¬ 

We have seen that the action of 
the tenotomized muscle is consider¬ 
ably diminished in consequence of the 
withdrawal of its insertion. It is 
still more so by virtue of the very 
character of this new insertion. In¬ 
deed, the union of the tenotomized 
muscle with the eyeball is in most 
cases far from being as intimate and 
firm as its original attachment. Its 
insertion is formed by a lax cicatricial 
tissue, which diminishes the influence 
of the muscle on the ocular globe. 

Lastly, the excursions of the eye i 
by fibrous expansions passing fron: 
orbital margin, AeAi. (Figs. 42( 

Left 1 

setting back of the internal rectus. 

limited, even in the normal state, 
e tendon of each muscle towards the 
w , x „ As they become more stretched with 

the retraction of the muscl^\{M^ become veritable check-tendons , or check- 
ligaments . (Lockwoods /NKs ligament, this check-tendon, follows the 
muscle that has been ^tjjack (Fig. 43, Ai), and, even though the muscle 
might contract still ^gith a certain energy, the ligament would neutralize its 
effort all the moro-ft^ause the setting back of the muscle has stretched it. 1 

We thus numerous circumstances concur to enfeeble the retro- 

posed mu^^^tl to diminish the action which it exercises upon the ocular 


Traite d’anatomie descriptive; Merkel, Handb. der ges. Augenheilk., i. 
y lo74, and Handb. der topogr. Anat., i. pp. 279 and 301; A. Graefe, Motilitaets- 
ngen, p. 152, 1880; Motais, Anatomie de l’appareil mo'teur de l’oeil, p. 145, 1887. 


globe, while its antagonist gains, so to speak, nothing positive in conse¬ 
quence of the tenotomy. 

Hence it is not surprising to find the motility of the eye considerably 
limited in the meridian of the tenotomized muscle. If, for instance, the 
excursions have before the operation amounted to sixty-five degrees in the 
horizontal meridian,—that is to say, fifteen degrees to the outer side and 
fifty degrees to the inner side,—a corrective tenotomy may reduce the nasal 
excursion to twenty degrees and cause only five degrees to be gained on the 
temporal side, so that the total excursion will no longer amount to more 
than forty degrees. Hence the eye will have lost in this way twenty-five 
degrees of its horizontal rotation. 

The field of fixation often shows no increase on the side opposite to the 
tenotomy, while a diminution on the same side always takes place. 

What we have said concerning an extensive tenotomy is still more ap¬ 
plicable to tenotomy reinforced by a conjunctival suture, and especially to 
the thread-operation of von Graefe. Such operations consist, as is known, 
in forcibly causing the eye to turn to the opposite side from the tenotomy, 
by means of the corrugation of the conjunctiva or the subconjunctival 
tissue, or by a thread one end of which is attached to the ocular globe, 
while the other is fixed at some point outside of the eye,—on the temple in 
our case. 

For almost twenty years now we have argued against this procedure, 1 
demonstrating that it may seriously injure the ocular movements in con¬ 
sequence of the falling forward of the globe in its muscul^Afunnel, and of 
the unfavorable insertion which it gives to the muscle &$|H)aJk. 

It is for these reasons that we recommend anckj^fctise muscular ad¬ 
vancement in preference to tenotomy. Instead of^r^eebling a strong mus¬ 
cle, we reinforce a weak one. wQ 

In the advancement of the muscle evj^pfing combines, indeed, not 
only to give to the eye its normal diremoV >n the primary position, but 
to augment the field of its excursion. 

The operation for advancement c^^ists in the detachment of the mus¬ 
cle from its normal insertion an^jfts reattachment by means of sutures as 
near as possible to the corneQvMore than one method may be used for 
this operation. We have^kk&ribed the one which we actually prefer in the 
Archives of Ophthah [1896). The essential points are to have a raw 
surface for the attac^m^nt of the muscle, to make the sutures include not 
only the conjun^tjja, but as much as possible the episclera, and to keep the 
patient in bedytotti eyes bandaged, until firm union has taken place. 

The l^q^R^nt action of muscular advancement consists, in the first 
place, augmentation of the extent of the muscle over the eyeball. 

^ndolt, Report of his clinic, 1878; International Medical Congress, "Washington, 
et seq.; British Medical Association, Dublin, 1887; International Congress 
Ophthalmology, Heidelberg, 1888 ; International Congress of Ophthalmology, Edin- 
►Nrnrgh, 1894; British Medical Association, Carlisle, 1896. 


The muscle thus has a more powerful action on the ocular globe, its inser¬ 
tion being brought nearer to the corneal border. It is carried, for instance, 
from e to e!. (Fig. 44.) 

By tenotomy the eye is more or Fig. 44. 

less expelled from the grasp of its 
muscles; the advancement, on the 
contrary, introduces it more deeply 
into its muscular funnel. 

The advanced muscle is almost 
always somewhat shortened. We 
even have the habit of cutting off its 
tendinous extremity whenever the 
strabismus exceeds a certain degree; 
thus we still further increase the trac¬ 
tion which the muscle exerts upon the 
globe of the eye. 

Finally, what we have just ex¬ 
plained concerning the influence of 
the check-ligaments on the tenoto- 
mized muscle is applicable, mutatis 
mutandis , to the advanced muscle. 

If, in the former case, the limiting 
action of the ligament stretched by 

the retracted muscle is felt very soon, t 

in advancement the ligament advanced with the muscle ^fiEfyts 
to contract to a much greater extent. JZT . . 

Let us consider Fig. 44. By advancing the extenmN’ectus, E , and thus 
carrying its insertion from e to e f , we have in tlmrfi mt place augmented by 
ee' the extent of the involution of this muscle,^2^f consequently its rotary 
action on the ocular globe. We can furtfieuiMy that we have sunk the 
latter by the amount of eie' in its muscuTunnel, which must necessarily 
bring about an increase of excursion in^e meridian of the operation. 

Again, the ligament Ae , whosq0^iterior extremity has followed the 
tendon of the muscle in its advafc^tfnent, thus permits the latter to con¬ 
tract more freely than in theA^lar state. 

For all these reasons^tkeymre, the excursion of the eye is always in¬ 
creased on the side of feelttavanced muscle. And a peculiarly fortunate 
effect is that one $egj^ has to regret a diminution of the motility to the 
opposite side. 

This fact in no way confuses us. It can only puzzle those who com¬ 
pare the n^A^^s of the eye to ribbons which act in virtue of their elas¬ 
ticity andmoVof their innervation. Thanks to this strange conception and 
to th^/ben|f in the immobility of the centre of rotation of the eyeball, 
sonp^pmalists suppose that the effect of the setting back and that of the 
a^aircement of muscles are identical. According to them, in setting back 
♦ /I . 

Left eye after advancement of the external 

Sts the latter 


the internal rectus, what is lost in excursion on the nasal side should be 
gained on the temporal side. We have already shown how erroneous this 
idea is, and how disadvantageous the setting back is for the movements of 
the ball. 

The converse is true of advancement. According to the theory still 
too popular, the temporal excursion of the eyeball should gain by the 
advancement of the rectus externus, but there should be an equivalent 
loss on the nasal side, because, as is said, the internal rectus has now a 
stronger antagonist. But one forgets that the external lectus opposes the 
internal only when it contracts, and it contracts only in answer to a ner¬ 
vous stimulus. Otherwise it is more or less limp and does not prevent 
the eyeball from turning in the opposite direction. So, in spite of the 
advancement of the external rectus of the left eye, for example, that eye 
will be able to turn towards the right as well as before the operation. Or 
why should the left external rectus contract when the eye turns to the right 

The same holds good for convergence. This function is not injured by 
the advancement of the external recti, because the nervous stimulus for 

convergence is directed essentially towards the internal recti and not 
towards the abducting muscles. 

In one word, in advancing a muscle, we gain on that side because we 
have won more favorable conditions for its action, and we lose nothing on 
the other side because we have left its antagonist intact. As a matter of 
fact, experience bears us out, and if the excursions of tWWes were meas¬ 
ured carefully before and after the various operations £5> .strabismus, there 
would be less discussion among the surgeons and l^fcjleception among the 

We practise muscular advancement alon^fejow and medium degrees 
of strabismus. If the deviation is a ^ ew degrees, ^ ma 7 

suffice to advance the external rectus S^eSzye which usuall y converges; 
but it is generally better to perfora^he same operation on both eyes at 
the outset. This way of doing is iQ , e logical than that which seeks to 
obtain the whole correction b\^J£>operation on a single eye, because, as we 
have pointed out, concomita^N^abismus is a binocular affection. 

Experience justifies^tif^ontention, moreover, by showing that this 
double advancementpa@u by the treatment which has been explained in 
the preceding para^^yjli, gives perfect results without any of the disadvan¬ 
tages of tenotoi <£> .. 

Above airVfe have never found occasion to regret the over-correction 
which Qrt^lGSsnly too frequently after tenotomy. It is for that reason that 
( we alwayVadvance the muscle as near as possible to the edge of the cornea. 
Nothings easier, as we shall see, than to diminish the effect of this opera- 
Specially in convergent strabismus. 

XA^As to the technique of muscular advancement, it is the subject of an- 
k <*>ther article of this System. It is not our jurisdiction to cite the multiple 



and varied methods of it. 1 For the same reason we only mention the opera¬ 
tions which, like capsular advancement (von Wecker) and the folding of the 
muscle (Knapp), act as weak advancements. 

What we have said in favor of muscular advancement must not be 
understood as implying condemnation of tenotomy. Although we never 
practise setting back alone in convergent strabismus, but give preference to 
advancement, even in strabismus of low degree, in certain cases of insuffi¬ 
ciency of convergence or difference in height between the two eyes, tenotomy, 
cautiously performed and combined with orthoptic training, may give satis¬ 
factory results. 

Sometimes we also have recourse to tenotomy in order to increase the 
effect of the advancement. But this is necessary only in the highest de¬ 
grees of strabismus, and especially in paralytic strabismus. 

Even in such cases, however, the muscle must not be set back very far. 
The conjunctival incision should be short, parallel with the muscle, in order 
to avoid retraction of the caruncle, and the muscle should be disengaged 
from its adhesions only to a very moderate extent. In a word, the ad¬ 
vancement ought always to predominate over the setting back of the 
muscles. And since it is not possible to foresee the ultimate effect of 
any strabotomy, we advise not to perform both operations at the same 
sitting, but to await the effect of the double advancement before practising 
a tenotomy. 

After any operation for strabismus, binocular bandaging is the rule. 
We have already set forth in our communication to the Congress at Wash¬ 
ington 2 that “ Just as strabismus is a binocular affectiqrf^Jie operation 
for strabismus is a binocular operation,” because, altho^gta it is performed 
on only one eye, it nevertheless always affects both. 

Binocular bandaging is peculiarly important^Nj^r the operation for 
convergent strabismus. Darkness, inactivity, tt&^b^ence of any object that 
might provoke an effort of convergence, bourne in this case, with atropini- 
zation, powerful orthoptic therapeutic agtenW' 

If the effect of the operation shotffepseem excessive, atropine may be 
suppressed; but one is not to be fingufened by even a marked divergence 
after advancement. It is formidflNsr>nly when the internal rectus has been 
tenotomized. O0 ** 

When divergence follo^v^enotomy, the muscle which has been set 
back should at once syttght for and advanced by a firm suture. This 
manoeuvre is easy, especially with our forceps, the jaws of which are oblique. 
(Fig. 45.) The uA^ment is therefore well adapted to catch the muscle 
for its tenotonwvand is no less useful for finding the set-back muscle. In 
the latter Anyone has only to reverse the forceps, so that its jaws are 
directed pjH^fcrd towards the conjunctiva. 

1 up 

T Vide our method in the Archives of Ophthalmology, xxvi., No. 1, 1897. 
3 Loco citato, p. 718. 


If the over-correction is due to advancement, it nearly always disappears 
entirely of itself and without the least prejudice to the positive part of the 
amplitude of convergence. The negative part—that is to say, divergence— 
is always augmented, and thus very favorably counterbalances the spasm of 
the adductor muscles. 

Fig. 45. 

Landolt’s forceps. 

As to the excursions of the eyes in the associated movements, we have, 
as said before, always found a considerable increase on the temporal side of 
the field of fixation without any loss on the opposite side. 

Hence in case of apparent over-correction after advancement one need 
not hurry either to do away with the binocular dressing or to remove the 
sutures. For the most part we let the threads remain six days and the 
dressing about a week, unless peculiar circumstances oblige us to leave one 
or both eyes uubandaged sooner. 

The surgical dressing is immediately replaced by lenses which correct 
the total hyperopia. These lenses should be large and of smoked tint, in 
order to shield the eyes from the dazzling resulting from the mydriasis. 

It is best, indeed, to continue the orthoptic treatment for a long time. 
The operation, by itself, by no means cures the strabismus; it is only a 
part of the treatment, a powerful aid lent to it. If not complete 

the cure by exercises tending to re-establish binocula^jiMon, by the train¬ 
ing of convergence and divergence, we shall nevei>^t a satisfactory result, 
or if we accidentally obtain it, we may soon lps^lOagain. 1 

It would take too long to enumerate herc*2tf"the difficulties which may 
be met with in the surgical treatment of^traNgmus. We cannot, however, 
remain silent concerning a somewh& n^quent peculiarity which is due 
to the disturbance of “ orientationthe deviating eye. It is a new 
proof of what we have always 1 m& 1, that the most perfect surgical correc¬ 
tion is not always sufficient, if the vision is good on both sides, to 
re-establish binocular viskd^Ptfe eyes have not only forgotten—if they 
have ever learned—to fus^vhe impressions of their foveae, but the visual 
centre of the deviattfi 'gfye may so accustom itself to the vicious direction 
of this eye that its retinal images are falsely projected . It happens, in¬ 
deed, as we hav£>ra2t above, that the part of the retina of the deviating eye, 
which receiy^hAie image of the object that is fixed by the normal eye, 
usurps t^XSvNertain degree the functions of the macula. It succeeds not 
iii musing its impression with that of the other eye, but it becomes the 
orientation for the deviating eye. 



1 Landolt, Le resultat ideal de Poperation du Strabisme, Societe de Medecine pratique, 
e>v Juin, 1889. 



Thus it is that one sometimes notices, after a perfectly successful opera¬ 
tion for convergent strabismus, that the patient complains of a strong crossed 
diplopia, as if he were affected with a high degree of divergent strabismus. 
If his former convergent strabismus amounted to twenty degrees, a part 
of the retina situated twenty degrees to the internal side of the macula had 
become almost equivalent to this macula. By the straightening of the eye 
the physiological macula has taken its normal place opposite the fixation- 
object, and the “ false macula,” as it has been called, like all other points 
of the horizontal meridian, has been carried twenty degrees inward. Now, 
if the patient continues to consider this latter part as the centre of his 
retina, he finds himself like one who is affected with divergent strabismus, 
and if he projects the retinal images of this eye accordingly, the image 
received at the anatomical macula will be referred to an object situated at 
the nasal side, where it would have needed to be in order to form its image 
on the macula while the eye was still deviating inward. In a word, one 
observes in this case a crossed diplopia analogous to that of paralysis of 
the internal rectus, and of a degree equal to that of the pre-existing con¬ 
vergent strabismus, if the correction has been perfect, or less if it has been 

On the other hand, it may happen that the eye cured of strabismus by 
operation projects at once with reference to the two centres of orientation. 
It sees the object whose image is produced in the physiological macula at 
the same time in its true position and on the nasal side,—that is to say, 
with monocular diplopia. Moreover, if neither of these two images is fused 
with that of the other eye, triplopia may result. Or, agaijrfske two kinds 
of projections may alternate. 

Monocular diplopia rarely persists. For the y^t^part, the normal 

operation has been 
follows and completes 

macula promptly resumes its function, especial 1\ 
correctly performed and if the stereoscopic trai< 
its effect. /y 

The same thing that we have justfporMm out may likewise be pro¬ 
duced in divergent strabismus. The ditfibpia which follows the operation 
is in this case homonymous , the fafcemacula being carried towards the 
temple by the straightening of tl^jre. 

Correct fusion and binocular ^vision being finally re-established, we 
cannot abandon our patientyvWe must guide him for some time yet in 
the use of his recovered^ureS; 

According as the, temiency to convergent strabismus is more or less 
abolished, and accdroSag to the age of the patient, we make him wear 
convex lenses ^qkrecting the manifest hyperopia (when mydriatics have 
become supei^wus) either constantly or for near work only. 

We do ajbay with them entirely if there is any tendency to divergence. 

W^^Bould resume, on the contrary, all the treatment of strabismus— 
ati^m^ation, correcting glasses, and repose of the eyes—if the convergence 


In this way one continues master of the situation until the strabismus 
is completely and radically cured. The result is then so perfect that not 
only does the individual enjoy all the advantages of recovered binocular 
vision, but there remains no vestige of the operation, unless freer excur¬ 
sions and an amplitude of convergence which is more extensive even than 
in the normal condition. 


As a rule, the eyes in a condition of complete repose diverge} 

There is nothing surprising in this fact; we have only to consider that 
the orbits diverge from each other at an angle of about forty degrees. 2 
(Fig. 10.) The abductor muscles encircle the ocular globes for a consider¬ 
able distance, as if they had followed the eyes in their forward rotation, and 
have almost an extended appearance owing to the exercise of convergence, 
a function which is an acquisition of the highest vertebrates only. The 
lower one descends in the series of vertebrates the more the eyes diverge, 
until finally they are found to be diametrically placed on either side of the 
head, as in certain fishes. 

However high the human race may be elevated above its ancestors, 
convergence still constitutes an effort. Abandoned to themselves, the eyes 
diverge. This is a law which admits of few exceptions. 

Convergence was evolved, of course, in the interest of binocular vision . 
It is, moreover, so intimately associated with accommodation that under 
normal circumstances an effort of accommodation suffices to provoke a 
convergence movement. 

However, if binocular vision and accommodation^jJ^lacking, the eyes 
place themselves almost invariably in divergence. />Tbat is why an ambly¬ 
opic eye—an eye that is useless—almost alwav^fiSdates towards the tem¬ 
ple, and why myopes, who exercise their qpd&unodation much less than 
emmetropes or hyperopes, furnish the large ii|ajority of divergent strabis¬ 


In myopia of high grade, diverg^^strabismus is the rule. The ellip¬ 
soidal form which such eyes assupe, and which is the cause of their ame¬ 
tropia, of itself tends to mal^Smem take the direction of the orbits, in 
which they are somewhal^sdl^y^odged. 

Their movements, Qfqwhilly that of convergence, are hindered, more¬ 
over, by the peculia£fcpn of the myopic eyeball. They are still further 
limited in consequence3f the elongation of their muscles; for, as Fuchs 3 
has demonstra^^ only that portion of the globe which is posterior to the 
insertion of /tfta-Anuscles participates in the elongation of the eye which 
prod uces^q^pia. 

p. 19. 

^^Xl^ording to Merkel, fortv-two or forty-four degrees ; Handb. der topogr., 


3 Fuchs, Archiv fur Ophthalmologie, xxx. 4, 1884, 1. 



According to Bonders, the angle gamma is particularly small in myopes. 
It may even become nil or negative,—that is to say, the line of sight may 
pass outside the optic axis. 1 We have found, as have also Dobrowolsky and 
Botto, that the angle epsilon comprised between the papilla and the fovea 
centralis (with its apex at the second nodal point) is likewise smaller in 
myopes, and that often, in spite of the increased volume of the eyeball, the 
distance between these two points is less than in emmetropia. It is evident 
that the nearer the macula is to the axis of the globe the greater must 
be the effort of convergence to direct the lines of sight towards the object 
of fixation. 

Hence it is seen that in this form of myopia several circumstances 
concur to render convergence difficult. This difficulty of convergence is 
the more troublesome, as myopes of high degree are obliged to bring the 
object very near in order to see distinctly. They are thus all the less 
apt to converge as they have more need of convergence in order to see 

Finally, by virtue of their static refraction such myopes have no need 
of accommodation in order to see distinctly even at a very short distance. 
The contraction of the ciliary muscle which causes the emmetrope to con¬ 
verge, even when one of his eyes is excluded, and which in hyperopia 
brings about exaggerated convergence, is lacking in a myope whose ame¬ 
tropia is of high degree. The convergence rendered difficult by the form 
of the eyeball is not excited by the accommodation. 

It is evident that under such circumstances binocular vision is either not 
developed or, at best, is developed in but a rudimentmt^Xay. Indeed, 
there is an advantage to the individual in suppressi^Nis completely as 
possible the visual impression of the eye which dopQSot fix, in order not 
to be troubled by the crossed diplopia resulting: ftrah the divergence of his 
visual lines. 

A person affected with a high degree qtfHw^pia brings the object within 
the region of the distinct vision of histeufcr eye without making an effort 
of convergence. The other eye divers? Even if the eyes were parallel, 
this parallelism would of itself rej^sent a considerable relative divergence, 
since binocular vision would oft^^require a convergence of ninety degrees 
or more. But for the mo^Km^^Ihe divergence is absolute . It exists for 
all distances and for all d/flyfcions of the gaze. 

That which happ^is^inevitably in extreme myopia very often occurs 
also in the case of ravopes of less degree. 

In. fact, the^H^mal relation which exists between convergence and 
accommodateqrf^ught to undergo, in the case of a myope, a considerable 
alteratiom^tra^ he sees without any effort of accommodation at a distance 
for which ne is obliged to use a comparatively great amount of convergence, 
— e.g his punctum remotum . 


Landolt, Refraction and Accommodation, p. 116. 



Thus, a myope of 4 D. sees clearly without accommodating at one- 
quarter of a metre (or twenty-five centimetres). But in order to see simply 
he must make a convergence effort of 4 ma. For all distances situated 
nearer than his punctum remotum the accommodation is less by four units 
than is the convergence. 


If the myope possesses an amplitude of positive relative convergence 1 
of 4 ma, binocular and single vision will be possible. If he does not have 
such latitude in his converging power,—if, in a general way, the degree of 
the myopia surpasses that of the amplitude of positive relative convergence, 
—there exists an insufficiency of convergence , unless the accommodation 
should enter into play in an exaggerated way, the effect of which would be 
to render vision indistinct. 

There are, of course, myopes the degree of whose ametropia is slight 
enough, or whose amplitude of positive relative convergence is sufficiently 
developed, for binocular clear vision to be possible at any distance between 
the punctum remotum and the punctum proximum without the use of cor¬ 
recting glasses. But the independence of convergence relatively to accom¬ 
modation is limited, and does not admit of a very high degree of ametropia. 
Beyond 5 D. discord between the two functions is easily established. 

It is true that this lack of harmony does not by itself constitute di¬ 
vergent strabismus. There exists only a relative divergence of the lines of 
sight for all points situated nearer than the punctum remotum , or rather a 
tendency to relative divergence, which is manifest only when one eye is 
occluded or when binocular vision is made impossible by 4^ use of a ver¬ 
tical prism or some other means. 

In virtue of this incongruity between the two fusions, however, con¬ 
vergence usually develops poorly with such pers^m^ for, unless endowed 
with a peculiarly great amount of converging# {Qker, the individual may 
find it advantageous to disregard the imajj^^pived by one of his eyes for 
the sake of escaping diplopia; in a wordQnJm&ular vision may not acquire 
a preponderant influence upon the rela^eairection of the eyes. 

If there be added to this a defeQ^e development or an enfeebling of 
the motor muscles, in consequej a debilitating illness, the individual 

will only too promptly abanck^^ie convergence which is troublesome to 
him. Let one of his eyesN&Pany reason, be inferior to the other, and he 
will no longer make aja*e|f^jrt of convergence which neither binocular vision 
nor accommodation rlmijtes of him. 

Thus we see the typical convergent strabismus—that of hyper- 

opes—is an ach spastic strabismus, divergent strabismus is an essen¬ 
tially pas.sw^Sbismus, due to a relaxation or to a lack of development of 

Although myopia, for the reasons just stated, furnishes the largest pro- 
po^RMi^f cases of divergent squint, yet it is found also in other states 

1 Landolt, Refraction and Accommodation, pp. 196-218. 



of refraction. We have already said that any cause which abolishes bin¬ 
ocular vision predisposes to strabismus. Now, the most natural deviation 
of the eyes is evidently divergence; it almost always corresponds to their 
position of repose, and consequently is accomplished without effort. It is 
for this reason that divergent strabismus is the rule in cases of monocular 
amblyopia or amaurosis. 

This fact is usually explained by saying that the amblyopic eye, not 
being able to collaborate usefully with its congener, becomes disinterested, 
so to speak, in vision, follows its own course, and deviates outward. This 
explanation seems to correspond with what happens daily, when we see 
divergent strabismus established, often in the course of a few months, in an 
eye which has suddenly become blind. However, this is not the proper 
way in which to consider this phenomenon. To be correct, we should say, 
binocular vision being abolished, the eyes no longer make the effort of 
convergence, which effort is useless and troublesome to them; they abandon 
themselves to a relative divergence, which gradually becomes absolute. 
Only, as one of the eyes is always directed towards the object to be fixed, 
the deviation manifests itself exclusively in the amblyopic eye. But 

Fig. 46. 

Fields of fixation of two strongly myo^^eyes affected with divergent strabismus. 

divergent strabismus is a 65ioa^^\strabismus just as is convergent stra¬ 
bismus. 1 

In the same way as the(e\amination of the field of fixation denotes in 

convergent strabismus o^Jj&ng standing a limitation of the temporal excur¬ 

sions in both eyes, s 

excursions towards the nasal side are always found 

limited in both e£$j^although only one, and always the same one, is the 
victim of di^m^STstrabismus. 

This cHm^^in motility is in both cases, in the majority of instances, 
not the c^isubut. the consequence of strabismus. In divergent strabismus 
it is dueV a lack of use of the adductor muscles, for which convergence 

1 Landolt, Archives cPOphtalmologie, 1807, p. 85. 


constitutes an exercise much more powerful than do the associated lateral 

Whenever we have had to speak of the relations between accommodation 
and convergence , we have taken care to remark that these relations have 
nothing absolute about them, and that consequently one cannot admit a 
single centre of Innervation as ruling them simultaneously. This con¬ 
clusion is proved by the classical experiments of Donders, as well as by our 
own, on the relative amplitudes of accommodation and of convergence; ex¬ 
periments which have demonstrated to what degree the two functions may 
be exercised independently of each other. 

This independence, moreover, is shown by the fact that the amplitude of 
accommodation gradually diminishes as age advances until it becomes nil, 
while convergence remains almost invariable during the whole life. Hence 
the relations between the two functions must be constantly modified ; other¬ 
wise binocular and distinct vision would not be possible even for emme¬ 
tropic eyes. The individual must learn how to associate the same degree 
of convergence with a greater and greater degree of accommodation. 

That, however, which is produced in one direction, for the sake of 
binocular vision, can quite as well be produced in the opposite direction, 
for the sake of the individual's comfort, when binocular vision is lacking. 
As long as the emmetrope fuses well the visual impressions of his two eyes, 
accommodation causes him to converge so correctly that he directs even 
the eye that has been excluded from vision towards the object fixed by the 
other. \ 

But if he loses the sight of one of his eyes, he learns Equally well to 
abandon the effort of convergence which is hence useless, although 
accommodating correctly. And if he notices tfiS^this insufficient con-: 
vergence no longer brings about, as it formj^ly did, the visual trouble 
resulting from the diplopia, nothing is mrfS^latural than that the con¬ 
vergence should be almost entirely abolifliea^> 

What is produced in the case ie emmetrope may equally well 
happen to the hyperope, although tH^ among them who renounce binocu¬ 
lar vision do so more often by auj0jenting convergence in order to facilitate 
accommodation. However, wQtave said before that this stratagem could 
not succeed with all hypAAQs. Indeed, not all of them are condemned 
to convergent strabisj^u^!^ Some of them, deprived of binocular vision, 
squint outward and ^mjisli a certain contingent (five per cent., according to 
Schweigger) of ^ligj^gent strabismus. 

Just as inynXTcase of convergent strabismus, local circumstances have 
been invoka^^g 7 capable of favoring the production of divergent strabis¬ 
mus. lave been supposed to be found in a vicious insertion , a de¬ 

fective* abielopment, an insufficient power of the adductor muscles , or, again, 
in tih&mvergence or in the excessive separation of the orbits. Smallness of the 
\mgmgamma has likewise been brought forward to explain the genesis of 
Jd^ergent strabismus among non-myopes. According to Stilling and others, 


certain eyes ought to be predisposed to divergent strabismus by their 
position of equilibrium , which, in these cases, is divergence. Another 
theory holds that it is a primary lesion of the centres controlling the 
symmetrical movements of the eyes which is the cause of this form of 

We have already mentioned these various attempts to explain the anom¬ 
alies of the relative direction of the eyes when discussing the etiology of 
convergent strabismus. We shall not further review the matter here, except 
to repeat that, although strabismus usually permits of a more satisfactory 
explanation, it is well to take all these circumstances into consideration. 

Divergent strabismus is often at first relative ,—that is to say, it mani¬ 
fests itself only under certain circumstances. While looking at a great 
distance, for instance, the eyes may be normally directed towards the object 
of fixation, especially when they are furnished with correcting glasses. 
Even if the object be brought nearer, they still follow it perfectly up to a 
certain point; but the attentive observer notices then that convergence seems 
no longer to increase proportionately with the approach of the object. 

Only one eye fixes it; the visual line of the other eye passes farther 
and farther from the object. Then comes a moment when this latter eye 
seems to hesitate as to whether it ought to converge or not; it still makes 
a few spasmodic efforts, then abandons the contest and deviates outward. 
This phenomenon is, on the whole, analogous to that which we can prove 
at any time on ourselves when the fixation-object approaches the pundum 
proximum of convergence. The only difference is that in pathological 
cases these phenomena appear sooner, because the punytpfl^roximum of 
convergence is farther away, the convergence feebler. 

It is noticeable also in such cases that, even when/hi^ft eyes are directed 
towards the object of fixation, they diverge as s^h*as binocular vision is 
made impossible, whether by covering either of*Sfc$reyes or by the use of a 
vertical prism. This beginning of diverarfTKV^rabismus is sometimes ac¬ 
companied by asthenopia, just as is insufficiency of convergence. It is, in 
fact, the same thing. The patients rmnplain of headache, of vertigo, of 
all sorts of visual disturbances wkicnMtorment them during near work. 
These phenomena are due to tljx^aggerated effort necessary for conver¬ 
gence, and also to the diploma^fhi^Ii manifests itself whenever convergence 
can no longer be maintaino^v^It is true that the patients rarely complain 
of double vision; the^copplain of seeing confusedly; letters seem to run 
into each other, lines^mb^, become confounded with each other, etc. But 
when we analyze sensations we recognize that they are very often due 
to the redujfiicatJ'OM of the letters looked at. 

This iiA^^stage of divergent strabismus may endure for a variable 
period,—nb^Khs or years. When there is myopia of somewhat high degree, 
the strabismus only too promptly becomes absolute, especially if 

one crM^e eyes be weaker than the other. It is established especially early 
ses of amblyopia of one eye, whether or not the other be myopic. 


However, one must guard against considering every divergence that is 
met with in an amblyopic eye as concomitant strabismus. Just as conver¬ 
gent strabismus may be due to paresis of one or both of the abductors, so 
divergent strabismus may have the paresis of an internus for its cause. The 
latter is evidently much rarer than the former," inasmuch as the internal 
rectus, belonging to a muscular group which is innervated by the third 
pair, is only very exceptionally alone the victim of paresis. Such cases do 
present themselves, however, and the rarer they are the more important it 
is to give them attention, so as to know how to recognize them. 

The differential diagnosis between concomitant and paralytic divergent 
strabismus might seem to be very simple. It is so in typical cases, where 
a well-defined diplopia increasing in one direction and diminishing in the 
other leaves no doubt as to the paralysis of an ocular muscle, while the 
absence of diplopia, the equality of the conjugate movements of the two 
eyes, the gradual development of the deviation, etc, characterize concomi¬ 
tant strabismus. But there exist cases in which the absence of binocular 

vision, because of the amblyopia of one eye, excludes diplopia,—that is to 
say, the most striking symptom of paralytic strabismus. In such a case 
we have recourse to measurement of the excursions of the eyes. If there 
be paralysis, limitation of the field of fixation will soon teach us not only 
the nature of the strabismus, but also which muscle is implicated. 

But when the strabismus is not very pronounced, the limitation of the 
field of fixation is often not sufficiently characteristic to establish the differ¬ 
ential diagnosis. 

I remember a case of divergent strabismus of this kind whicflWas all the more puz¬ 
zling because it occurred in a girl sixteen years old,—that isO^Jsay, at an age when 
muscular pareses are rather rare. One of her eyes was myojrfl^OTid amblyopic, the other 
emmetropic and endowed with good visual acuity. The/frt?fergence of the defective eye 
seemed quite natural, according to the etiology of this^xj^of strabismus which we have 
just given. 

One thing, however, which was striking abo \t l/ isVase was a power of convergence 
extraordinarily well developed relatively to thStlegree of strabismus. 'When the patient’s 
attention was attracted energetically to a n^^object, she succeeded in converging in a 
truly astonishing way. Since binoculai>^ision was lacking, it was impossible to ascer¬ 
tain whether or not the convergence wd^Lrrect. 

I then covered the good eye aaJkAide the patient fix a candle-flame with only the 
squinting eye. What was at fl^st JCry strange was that the patient, instead of directing 
the eye promptly towards the^fajptet, left the eye in the divergent position and declared 
that she saw nothing, 
making her direct the dise! 
she saw the object 
direction opposite 

on stimulating her visual energy, I succeeded in 
eye towards the object; but, on asking her at what point 
wed us by extending her hand, not in front of her, but in the 
r strabismus. * Hence there was false projection. This false pro¬ 
jection is, as*I^fh^f above explained, due to a disproportion between the innervation 
brought intO^eWfei and the effect of the muscular contraction. It establishes a paresis of 
the muscle^^wch, to effect a given rotation of the eye, requires a larger amount of inner¬ 
vation ^iVn in the normal state. 

^OTkcJpfect in orientation, this erroneous localization of objects fixed by the imperfect 
, wM again manifest when I induced the patient to try to touch rapidly a pencil-point 
fed before her. 



Thus, when from the form of the diplopia and from the examination 
of the movements of the eyes we learn little or nothing as to the nature 

of the strabismus, then the projection—the muscular sense—may furnish 

us with decisive indications with which to establish the differential diagnosis 
between concomitant and paralytic strabismus. 

When the deviating eye is amaurotic, or when it has acquired the habit of 
fixing with an eccentric part of its retina, this symptom is evidently lacking; 
but the strabismus is generally very marked in such a case, and when one ex¬ 
amines the field of fixation, which is possible, even for an amblyopic eye, by 
means of the corneal reflex, one almost always finds a limitation in both eyes 
in concomitant strabismus, while the excursion of the deviating eye is much 
more limited in paralysis. 


In the beginning of this chapter we considered the movements that the 

two eyes are accustomed to execute together for the requirement of binocu¬ 
lar vision. Whatever may be the origin of the nerves 
controlling these movements, whatever may be the muscles 
which participate in them, clinical study has shown that 1 Tc ] 
the associated movements may be altered as such. Let us ji • 

recall merely the paralyses of the associated lateral move- !• i 

ments and those of the raising and lowering of the eyes. ji [ 

The same thing is produced much more frequently still j 1 j 

for the adduction of the eyes,— e.g. y for convergence. j \ j 

Although von Graefe, A. Graefe, Horner, and others J j | I 
had already known and pointed out a form of asthenopia i i! 

due to the impossibility of converging sufficiently, it Mil 

Krenchel 1 who in 1873 clearly established that j i i ^ 

the power of convergence we shall have to study this function more closely. 

I have dqAroped by the term convergence 2 the faculty of directing the 
two eyes to>^3s the object of fixation, whether this object be situated at a 

1 Ueber die krankhaft herabgesetze Fusionsbreite als Ursache des Schie- 

lens^Ar^/ f. <Ophth., xix. 1, S. 142, 1873. 

^j*andolt, Insufficienz des Convergenzvermogens, Heidelberg meeting, 1885, and 
ction and Accommodation, translated by Culver, Edinburgh, 1886. 

Vol. IV.— 9 


finite distance, at infinity, or even beyond infinity,—that is to say, whether 
its fixation requires actual convergence, parallelism, or divergence. 

The most natural method of measuring convergence is by means of an 
object of fixation placed in the median line {MM', Fig. 47). In this way 
the angle of convergence is always the same for each eye. This angle evi¬ 
dently gives the measure for the convergence effort put forth by each eye. 

In distant vision, the two eyes (0 and O') having a parallel direction, this 
angle is nil. It increases in proportion as the object fixed is brought nearer. 
It may be said, then, that the angle of convergence is in inverse proportion 
to the distance between either eye and the fixed object in the median line. 1 
If the object be at Cat the distance OC= C, the angle of convergence 

JOC can be expressed by c = ^-. 

If we measure this distance C by the aid of the metre, we obtain for the 
convergence required in binocular fixation an expression identical with that 
for the refraction necessary for distinct vision of the same object. 

Thus, supposing an object to be situated at a distance of one metre 

from each eye, there must be for both eyes — = 1 dioptry of positive re¬ 

fraction and ^=1 unit of positive convergence. 

This unit is called, after Nagel, to whom we are indebted for this prin¬ 
ciple of measurement, the metre-angle . 2 

For our purpose, 

1 In reality this ratio is not the angle of convergence, but its^m~. 
however, we may conveniently substitute one for the other. 

2 This expression is analogous with metre-lens, which NagiC^is proposed for the di¬ 

optry. The absolute value of the metre-angle depends upon^^Tlistance (base-line) which 
separates the centres of rotation of the eyeballs fronuei^VSther. For instance, if this 
base-line is 58 millimetres in length, the metre-angle 39/ 39// ’ say 10 ° T 10()/ ’ 

For a base-line of 64 millimetres the metre-angle>5>^50 / ; say 110', and so on. (Nagel, 
in Graefe-Saemisch Handbuch, vi. p. 478.) ^ 

The following table gives the equivalenf^between degrees and metre-angles (M.A.) 
for the two values of the base-line. 


58 mm. 


64 mm. 

M.A. Degrees. 

M.A. Degrees. 

0.5 = 0° 50 

0.5 = 0° 55 

1 = 1° 40 

1 = 1° 50 

2 = 3° 20 

2 = 3° 40 


3 = 5° 30 

4 = 6° 40 

4 = 7° 20 

5 = 8° 20 

5 = 9° 10 

6 = 10° 

6 = 11° 

7 = 11° 40 

7 = 12° 50 

8 M 13° 20 

8 = 14° 40 

9 = 15° 

9 = 16° 30 

10 = 16° 40 

10 = 18° 20 

11 = 18° 20 

11 = 20° 10 

12 = 20° 

12 = 22° 



If the object is placed at one-third of a metre from each eye, 


= 3 D, 

and 3 ma are required, and so on. 

The amplitude of convergence is obviously contained between the maxi¬ 
mum and the minimum of the convergence which an individual is capable 
of exerting. 

The maximum of convergence is inversely as the distance of the nearest 
point, punetum proximum of convergence , which can be fixed binocularly. 
If P be the distance which separates this point from each eye, the maximum 

of convergence is = — 

In measuring the distance P by means of the 

metre, we can replace this fraction by the value of p metre-angles. 

The minimum of convergence , upon the same principle, is inversely pro¬ 
portional to the distance which separates each eye from the farthest point 
which can be fixed binocularly. If E be the distance of this punetum 

remotum of convergence, the minimum of convergence will be i = r ma. 


If this latter point be situated at a finite distance, the minimum of conver¬ 
gence is positive, and can be determined in the same manner as the maximum, 
as I shall hereafter explain. But this happens only in pathological cases. 
Under normal conditions the lines of fixation can be directed at least paral¬ 
lel with each other. The minimum of convergence in such a case is equal 

to zero, because the punetum remotum is situated at infinity and r = JL 0. 

Most normal eyes, however, can diverge more or less. The minimum 
of convergence is then negative . It is always inversely proportional to the 
distance of the punetum remotum , only, as the lines of faragtoir diverge, this 
point is situated not in front of the head, but bebn^Wt (— R , Fig. 47), 
where the lines of fixation, prolonged backward, 

The amplitude of convergence (a) is represen&^fefy the difference between 
the maximum and the minimum of this fij 

function : 

* =p & 

In normal cases I have found >&at, on the average, the minimum of 
convergence is about —1 ma, thQuaximum 9.5 ma, and the amplitude of 
convergence, therefore, 10.{ 

When the minimum cwMbhvergence is negative , its amount is measured 
by the strongest abdu(^nj[ prism which can be overcome in distant vision. 
We have, however, tv bear in mind that, although the prism be placed be¬ 
fore one eye only^A^rcts, notwithstanding, upon both. Hence the value of 
the prism ha^ tmW divided by 2, in order to obtain its deviating action for 
each eye. 

light w^Jtrit 

forism is numbered—as is desirable—according to the angle of the deflection of 
light v^llrit produces, it suffices (for children whose base-line equals 58 millimetres and 
1 mek’e-angle = 10(F) to multiply this number by 3 and to divide the product by 10, in 


order to obtain the corresponding number of metre-angles. Thus, a prism of five degrees 

will correspond to = 1 .5ma. 

For adults, in whose case, because of the greater separation of the eyes (64 millimetres), 
the absolute value of the metre-angle is greater (110 7 ), the formula becomes if we desig¬ 
nate by x the number of degrees to be converted into metre-angles. Five degrees corre- 

spond, in this case, to -yp— = 1 .Zma. 1 

In the normal condition positive convergence ought to amount to at 
least 9 ma; in other words, the eyes ought to be able to fix easily an object 

P (Fig. 47) situated at a distance of -y =11 centimetres from them. 

On the other hand, they'can diverge about one metre-angle,—that is 
to say, to such an extent that their lines of sight meet at —R (Fig. 47), 
one metre behind the head. 

Fig. 48. 



2 - 

- t~ 



- i. 

2 - 

4 . 

5 . 

6 . 




10 ---- 

11 - 

12 —- 

2 $^ 





We can represent th^ amplitude of convergence graphically, as is 
shown by Fig. 48. I^h^piagram the range of convergence is represented 

1 If the prism be numbered according to the method formerly used,—that is to say, 
according to its apoe^Cwe,—we have to divide the number of the prism by 7 to ob¬ 
tain for each eye, ifnS^tre-angles, the rotation required to overcome it. The distance be¬ 
tween the two^e^^ir this case, is admitted to be between 58 and 64 millimetres. A prism 

of No. 14 ^^^nzontally before one eye requires from each eye a rotation of ^ — ‘Ima 

adduction >uf fhe apex of the prism is turned inward, abduction if the prism-apex is turned 
outwan^VA person who, during distant vision, can overcome an abducting prism of old 

i^L^^as a divergence power— r=~=.71ma. 


by vertical lines. The full horizontal line indicates zero ma, —that is to 
say, it corresponds to parallelism of the lines of sight. 

The part above the horizontal represents negative convergence (or diver - 
gence ), the part below the horizontal represents positive convergence. 

The figures and dotted lines indicate metre-angles. Hence the line A 
represents the normal condition of the amplitude of convergence, the posi¬ 
tive part p = 9 ; r = —1 ma. 

It might appear that nature, which in the distribution of our functions 
is generally so parsimonious, had been almost prodigal in endowing us with 
nearly 10 ma of convergence,—that is to say, in permitting us to converge 
for a distance at which we never work. No such prodigality has been 
shown, however. In this case, as in the others, we have received only what 
is strictly necessary : the punctum proximum represents, indeed, the maxi¬ 
mum of convergence of which an individual is capable. Now, in order to 
continue any muscular effort for a long time, it is essential that this effort do 
not require from the outset all the force that is at its disposal. 

No eye maintains for more than an instant vision at the distance of its 
nearest point of accommodation, for the very reason that vision at that 
distance requires the maximum contraction of its ciliary muscle. In the 
same wav, nobody can maintain convergence at its maximum without 
crossed diplopia immediately showing him that his power of adduction is 
exhausted. The mere mention of these facts suffices to prove that the 
position of the punctum proximum of convergence does not ^correspond to 
the distance at which the individual can work, nor the j^bum of con¬ 
vergence the power which would be at his absolute irahiosal during the 
continuance of his occupation. Of this force he ca^^mike use of only a 
relative quantity, while he must have a certain ammtait in reserve to replace 
the force expended. 

It is of primary importance to be acqu^inteS^with the relations between 
the quantity at disposal and the totality ofctlnSTunotion, to know, there being 
given, on the one hand, the distance at^vwich a person wishes to work, and, 
on the other, his power of converger^, whether or not the latter is sufficient. 

We have tried to determine quota of convergence , l and our experi¬ 
ments seem to demonstrate f^W^i^reserve amount ought to be about twice 
as great as the convergenc^njqhired by the work. 2 

March, 1886, Insufficiency of the Power of Con- 
1886; Bericht der Ophthalmologischen Gesell- 


1 Landolt, Arch. ^’Wnhthalmologie, 
vergence; The OphtJ*|taMC Review, v., 
schaft, Heidelberg-^SJ. 

2 It is into^A^to note the difference which exists, in this regard, between conver¬ 
gence and a^^OTnodation. We have found, indeed, that one-third of the amplitude of 
accommodation suffices for the reserve, while two-thirds of the amplitude are necessary for 
the r&gc^Aart of convergence. 

■ ^ItN^/more than fifteen years since we undertook our investigations concerning the 
res^nte amounts of convergence and accommodation. Their results seem mutually con- 
ramtory. It must not be forgotten, however, that conclusions from experiments with 
scles generally, and with the ocular muscles particularly, may be somewhat uncertain. 



Thus, in order to work at the usual distance of -y, that is to say, with 

3 ma of convergence, 2x3= 6 ma should remain in reserve. In other 
words, the individual should possess at least 3 + 6 = 9 ma altogether. 
Hence we have here just the 9 ma that we found at the outset. They 
thus represent the amount which is strictly necessary for usual work. 

It is true that in this case, as in others, there are people who are much 
more fortunate, privileged ones who have at their disposal a much greater 
convergence capital (and who do not even always use it). But along with 
them, there are also the unfortunate whose convergence is not sufficient 
even to accomplish the daily work,—indeed, does not even allow them to 
use their eyes in any way without fatigue. 

We designate this condition as insufficiency of convergence. 

It is easy to see that, in spite of the normal amplitude, convergence may 
be insufficient for exceptionally near work. Thus, in order to woik at 

25 centimetres, or that is to say, with 4ma,—3 X 4 = I2ma of positive 

convergence are requisite. He who possesses only 9 ma will evidently be 
incapable of doing this work binocnlarly, and will feel the phenomena of 
fatigue which characterize insufficiency of convergence. But in such a case 
the insufficiency is only relative; it is not the symptom of a morbid con¬ 
dition, although claiming at least the optical aids that we use at times to 
remedy pathological insufficiency. \ 

Insufficiency of convergence properly so called i^^tS^cterized by a 
diminution of the positive part of the am pi itudej^bon vergence. The 
pundum proximum is farther away, and converge^fer greater or less dis¬ 
tances is difficult and gives rise to those symjffc^Ehpff asthenopia which are 
encountered in the early stages of diverge^^trabismus,—viz., fatigue of 
the eyes, crossed diplopia, pains in the h ^tty l^ving their seat especially in 
the forehead, vertigo, and general mafyiser 

When one examines, as is indisputable, not only the positive but also 
the negative part of the ampli^e of convergence, it is found that this 
function may be altered in vlu^yus Avays, and differently at its two ex¬ 
tremities. ww 

Thus, as the line B of our diagram (Fig. 48) shows, the total amplitude 
may have a normal (al^e of 10ma, and yet there may exist an insufficiency 
of convergence, tjjjj* maximum of convergence being only 7 ma. The two 
metre-angles AvhSti are wanting in the positive part are, so to speak, car¬ 
ried over to thcnegative: divergence is increased by the same amount that 
converg^^properly so called, is diminished. The entire amplitude has 
passed wm- toAvards the negative side. 

yfe^other cases (C, Fig. 48) the diminution of convergence is more 
Vnarced than is the increase in divergence. 

Sometimes the latter is normal (D), and the former alone is altered.—In 
. E, the opposite is the case. 



At times, also, convergence and divergence are both restricted {F, G, K). 

It may even happen, as in i, that the whole amplitude of convergence is 
negative. The individual can no longer converge, he cannot even give his 
lines of sight a parallel direction. He is subject to divergent strabismus. 
By bringing into action his entire adduetive power, he succeeds, at the very 
utmost, in not letting his eyes diverge more than half a metre-angle. On 
the other hand, he can increase his divergence even to 3 ma. Hence he 
possesses a certain amplitude of convergence : it amounts to 2.5ma; but its 
whole extent is negative. This “convergence” is therefore only a less or 
greater divergence. 

Insufficiency of convergence has very different causes . It may, in the 
first place, be the consequence of a material lesion of the brain or of the 
spinal cord. Thus Parinaud * 1 has found it in a case of neoplasm having its 
seat at the outer edge of the right cerebral peduncle and extending to the 
cerebellar peduncle, to the fourth ventricle and to the aqueduct of Sylvius, 
where it affected the nucleus of origin of the third pair. The same author 
reports, in the same place, a case of insular sclerosis in which, as he says, 
“ le mouvement de convergence sefaisait tr£s incompUtement an deld de 30 cm., 
la vision associee n’existe plus, die developpe du strabisme, et Von constate 
tons les signes d’une insuffisance prononcee des droits internes, en couvrant 
alternativement chaque ceil” 2 

In 1885, 3 along with Dr. Huebscher, then my chef de clinique, I 
observed a case of tabes dorsalis in which convergence was considerably 
limited. This case is reported with others in a monograph on paralysis of 
convergence published by another of our students, Dr. Baj^l, 4 in the Archives 
d’ Ophtalmologie. Similar cases have been published^by ae Watteville, 5 
while Granger Stewart 6 has seen a crossed diplop^yroduced during the 
movement of convergence in the case of an atasSW Gowers, 7 Samelsohn, 
and Stolting and Bruns 8 likewise mention thp;loss of the convergence move¬ 
ment in tabes. / W 

Since these publications attracted duNauention of physicians to the in¬ 
sufficiency of convergence in locom^m^ ataxia, observations of this kind 

have become very frequent. ^ 

1 Parinaud, loc. cit., p. 162.a franchise d’Opht., 1886, p. 23. 

2 Parinaud, Arch, de Ne^^ie, 1883, p. 162. See also Soc. franchise d’Opht , 

1886. /T C/ 

3 Landolt, Die Insufecijnz des Convergenzvermoegens, Heidelberg. Ophth. Gesell- 
schaft, 1885; Soc. fram*. cTOpht., 1886, and Ophthalmic Review, v , July and August, 
1886 ; Traite compl^^^pht., iii. p. 923 ; Refraction and Accommodation, p. 504; Stevens, 
Functional Nervo^^plseases, New York, 1887, Archives of Ophthalmology, xv., 1887. 

4 Borel, Paralysie de la convergence dans 1’ataxie locomotrice, Arch. d’Opht., No- 

5 A. dS^Vatteville, Ueber die Laehmung des Convergenzbewegung des Auges im 
BegininAdes Tabes Dorsalis, Neurolog. Centralblatt, No. 10, 1887. 

N^Nraliger Stewart, Eye Symptoms in Locomotor Ataxia, Brain, ii. 

7 Gowers, Diseases of the Nervous System, i. p. 298. 

8 Stolting u. Bruns, Graefe’s Arehiv, xxxiv., 3, p. 92. 


In fact, it is easy to understand that the affections of the nervous 
system, whatever their nature may be, can produce alterations of this kind. 
After simple insufficiency of convergence they may even bring about the 
complete abolition of convergence. 

A somewhat different form of insufficiency of convergence is that which 
accompanies the neuroses , and in particular what is called neurasthenia. 
We have applied to it the adjective neuropathic} 

Here again the excursions of the eyes may be normal; the synergy of 
the abductors (divergence) is at times normal (D, Fig. 45), or it may even 
be augmented (( 7 ) ; only the adduction has suffered. One often finds, how¬ 
ever, in such cases, that the range of convergence is reduced at both ends, 
as is shown at F and G of Fig. 45. 

In this category must be placed the insufficiency of convergence observed 
in exophthalmic goitre , 1 2 chronic alcoholism , hysteria , 3 and neurasthenia . 4 

Let us recall our observation reported in the paragraph concerning the 
associated paralyses, wherein an almost absolute insufficiency of conver¬ 
gence accompanied, in the case of a hysterical woman, abolition of the power 
to look up or down. 

Neurasthenia, while it is particularly frequent among women, neverthe¬ 
less also attacks the sex which merits so little the name of the “ strong.” 
It often has as its cause intellectual or physical strain, excess of work, 
of care, and also excess of pleasure. In this case, one is often much sur¬ 
prised to find a man of splendid figure and remarkable strength, apparently 
quite healthy, gifted with two perfect eyes, but yet incapable ®f using them, 
as a severe asthenopia manifests itself whenever he tries reading, 

or work of whatever kind at a short distance. 

I have met many cases of this sort, especially ^ir 
and I find an explanation of them in the ardoi; 
illimitable resources, characterizes the struggl^?h 
fortune and what it brings. 

American clientele , 
i, in that country of 
only for life, but for 

1 Landolt, Ophth. Gesellschaft, Heidelbcrj ^ 885. This insufficiency of the innerva¬ 
tion of the adductors, or, briefly stated, o^p^onvergence, constitutes a phenomenon analo¬ 
gous to the insufficiency of the orbicukTmjCTiat Rosenbach has pointed out and Bannas 
(Thesis, Breslau, 1893) has confirmeptpQharacteristic symptom of neurasthenia. 

2 P. L. Moebius, Ueber Insufc^pz der Convergenz bei Morbus Basedowii, Central- 
blatt fur Nervenheilkunde, 1 ££qOj^56. 

3 Borel, Affections hysl|'riqtes des Muscles oculaires, Arch. d’Opht., 1887, p. 356. 

4 Compare, among ojjiere^- 

Henry D. Noyes,'*jjjjplses of the Eye, p. 88. 

C. Stedman Bu^^n Soelberg-Wells, Diseases of the Eye, p. 719, fourth American 
edition. ♦ 

Th. R. 3^^J^New York Medical Journal, 43, p. 179. 

R. J. Mc^jfcy, American Journal of the Medical Sciences, October, 1882. 

C. JV^Culver, Convergence Anomalies, Albany Medical Annals, viii. p. 137, 1887. 

John Roosa, Medical Record, New York, p. 429, 1890. 

^^Cross, Bristol Med.-Chir. Journal, 1893, p. 73. 

ye Lapersonne, Recueil d’Opht. 



At times, also, this weakness of the adductive power accompanies anae¬ 
mia , or it remains as a vestige of some debilitating disease, —typhoid fever, 
influenza, difficult aecouchements, hemorrhages, etc. 

If this form of asthenopia can strictly still be called central , because it 
finds its explanation in weakness or in a lack of energy of the centre of 
innervation of convergence, we may hesitate to apply the same name to a 
third form of insufficiency of convergence, which is not rare, and which is 
essentially due to a lack of use . 

The type of this form of insufficiency is represented by myopes, of 
whom we have already spoken, who possess good eyes so far as their visual 
power as well as their motility is concerned, but which diverge as soon 
as the possibility of fusion is abolished, whether by the exclusion of one 
eye, by a vertical prism, or by any other means. 

With them convergence is weak, rudimentary, insufficient, because one 
of the stimulants which cause the emmetrope or hyperope to converge, even 
when there is no fusion,—that is to say, the accommodation,—is lacking. 

This is clearly proved by our measurements of the amplitude of con¬ 
vergence. 1 These show that even myopes whose binocular vision is intact, 
frequently have an amplitude of convergence which is inferior to that of 
emmet ropes; the punctum proximum is farther away than in the case of 
hyperopes or emmetropes, and, although abduction is often augmented in 
myopes, adduction is almost always restricted. If there be added still 
another circumstance which interferes with binocular vision, we need not be 
astonished if convergence is not normally developed in such dases. 

That which is the rule with myopes whose myopia is o&C^rtain amount 
may, as we have demonstrated, happen to eyes of any kind of refrac¬ 

tion, if the convergence is not often or not energet-v^ffiy exercised, in spite 
of an otherwise satisfactory development of thed^jamlar apparatus of the 
eyes * 

We see that this form of insufficiency onconv&rgence is essentially due to 
a lack of exercise . It is, in our opinion,^ot comparable to the insufficiency 
resulting from a central lesion ; it is id(^> wise a paralysis. 

Let us suppose the case of a vh0fous man with good legs. He is put 
on a horse. While at a walk, hcCJfcq well enough in the saddle, but as soon 
as the horse trots he wabble^undJ loses his balance. We recommend him 
to cling with his legs; h lis best, but at the first turn, at the least ac¬ 

celeration of the pace, \£jjie least shy of the horse, he falls. Do we com¬ 
miserate him, expl^i^jg to him that he is the victim of a cerebral affection, 
of a lesion of tk^veentre of innervation of his adductors? Not at all. 

w th a 

Though we kn^^fhat the adductor muscles do not contract without in¬ 
nervation, ^M^mat their centre of innervation is in the brain, we content 
kwmi s i 





saying simply that he is not in the habit of using the ad- 

Landolt, in Ellaby, Paris Thesis, p. 68, 1884, and Amplitude de Convergence, 
\ d’Opht , March, 1886. 


ductors of his legs. We encourage him, convinced that, with practice, his 
muscles, as well as their innervation, will be strengthened, and that he will 
finally be able to cling with his legs as much as is necessary. 

The same thing happens in the case of insufficiency of convergence of 
our third class; convergence is defective because it is not exercised. But 
we do not think that it can be counted in the class of the insufficiencies 
of central origin, for this term is generally understood to imply a material 
cerebral lesion. 

Finally, the fourth form of insufficiency of convergence is represented 
by cases wherein the internal recti muscles are really weak, in which the 
fields of fixation show a limitation at the nasal side. It is the muscular 
insufficiency which gives rise to muscular asthenopia when binocular vision 
exists, but to divergent strabismus when it does not exist. 

The existence of this muscular insufficiency has been denied, 1 as if the 
ocular muscles alone among the muscles of the human body could neither 
be nor become insufficient for the work which they have to accomplish, 
however hard that work may be. If, instead of making theoretical sys¬ 
tems, trouble were taken to thoroughly examine patients, notably their 
fields of fixation, such a statement would not be made. Even the fatigue 
resulting from convergence which has been too long maintained ought of 
itself to be able to bring about an insufficiency, at least a transient insuf¬ 
ficiency, of the muscles which cause convergence. 

On the other hand, we see that in cases where convergence is little used, 
not only does this function remain or become rudimentary^fyit the muscles 
also become weak. Thus it is that with myopes the of fixation are 
very often limited at the nasal side. This might (xj^^jon surprise if one 
thought that, although not contracting much for ^Vergence, the internal 
recti are nevertheless exercised in the associatd^)ateral movements. But 
we have already seen that the usual later^<(?^ions are of only a few de¬ 
grees, and are not comparable, either as\to/e&ent or as to duration, with 
the exercise to which these muscles subjected during convergence, in 
the interest of binocular vision. £Dthis form the insufficiency of the 
adductor muscles is secondary . 

But is there not also a >>runary muscular insufficiency, due to a con¬ 
genital defect of developffi^^f one or even of a group of ocular muscles? 
Such an anomaly is other parts of the body; why should the eyes 

be exempt from it? V-/ 

Fuchs has ahfoly demonstrated in a remarkable monograph 2 certain 
differences whi^TNfnay exist in the disposition of the ocular muscles. Le 
Double h^^mished in the Archives $ Ophtalmologie another work which 
is still w Conclusive in this respect. 3 

among others, International Congress of Medical Sciences, Berlin, 1890, section 


2 Fuchs, Arch. f. Opht-, xxx., 4, S. 1, 1884. 

3 Le Double, Arch. d’Opht., p. 218, 1894. 



Hence we may admit, in addition to insufficiency of convergence due 
to central lesion , to neurasthenia , or to lack of exercise , one due to defective 
development of the adductor muscles . 


Since the time of the illustrious von Graefe, many more or less com¬ 
plicated procedures have been invented for the examination of convergence 
and its anomalies. 

Thus it has been proposed to measure the converging power of an indi¬ 
vidual by making him fix first a distant object, and then a near one through 
adducting prisms. The strongest prism that he can tolerate without seeing 
the object double is supposed to measure his power of convergence. 

Fig. 49. 

J^P^lt’s ophthalmodynamometer. 

►It’s ophthalmodynamometer. 

It has also been Qgjjfcr ted that the best means of estimating the con¬ 

vergence power individual is to measure his power of divergence. 1 

To us, hos^ej^r, it has always seemed that, if one wishes to know a 
person’s pp^Nof convergence, the simplest and the most logical method is 
to detei svthe distance of the nearest point to which he can converge. 2 

InVirdbr to know whether convergence is normal or not, the value thus 


^-Mannhardt, Arch. f. Ophth., xvii., 1871. 

2 Landolt, Soc. fraru^aise d’Opht., 1883; Ophthalmic Review, 1886, p. 203. Re¬ 
fraction and Accommodation, d. 283. 


found has to be compared with the value found in the same way in healthy 

The instrument that we have devised for the estimation of the power 
of convergence (as well as that of the accommodation) is known by the 
name of ophthalmodynamometer. It consists of a cylinder (Q Fig. 49) 
blackened on the outside, which can be fitted on a candle ( B ) of ordinary 
size. The cylinder has a vertical slit about a third of a millimetre in 
breadth (Fig. 49), a series of fine openings which form together a vertical 
line, and a circular aperture about one millimetre in diameter. The slit 
and the openings are all covered with ground glass. When the candle is 
lighted, they constitute luminous objects of fixation. Beneath each opening 
can be attached one end of a tape measure that is rolled up by means of 
a spring. The tape is graduated on one side in centimetres, on the other in 
the corresponding numbers of metre-angles (or, what amounts to the same 
thing, in dioptries). 

To determine the maximum of convergence , we use the luminous slit as 
the object of fixation. The tape measure is drawn out to about seventy 
centimetres, its case being held beside one of the eyes of the jDatient (theo¬ 
retically, on a level with its centre of rotation), while the object of fixation 
is placed in the median line. If the patient sees the object single, then, by 
pressing on the knob of the case, the spring is made to roll up the tape, 
and thus the observer brings the fixation-object nearer to the eyes, taking 
care, however, that it always remains in the median line. So soon as the 
person under observation begins to see double, the near pw^yi convergence 
is attained. In fact, when the eyes have no longer the^pN^er required to 
fix the object simultaneously, there exists a diverg^r relatively to its 
position, and, consequently, crossed diplopia. 

At this instant, one side of the tape gives msfrnimetres the distance of 
the punctum proximum of convergence, andiffiV^ier side the corresponding 

F#r ins 



maximum of convergence in metr e-angles. Fo/ instance, eleven centimetres 
correspond to nine metre-angles. 

As the motor apparatus of the^es^does not always perform its func¬ 
tions with as great accuracy as i&Jftesirable, it is necessary to repeat the 
experiment several times at and, especially in pathological cases, 

on different days. 

It is furthermore tfnppdant, during all the time that the object is 
being brought nearer tVtfi courage the patient energetically to fix it. It 
will also be obsenj&Dthat the punctum proximum of convergence, when 
thus obtained, K^Oearer to the eyes than when the object is first placed 
within this j&i^ice and then withdrawn from the patient. By the latter 
method acc^^tfe results are not obtained. Hence we advise that the object 
of fixati^ft be brought toward the patient from a point for which he can 
ea Wge. 

Qjfere, as in all investigations concerning binocular vision, it may happen 
the patient is not certain at first whether he sees double or not. In 


cases, for instance, where one eye is considerably weaker than the other, the 
patient easily overlooks the retinal image of the former, so that he does not 
see double, notwithstanding a faulty direction of the eyes. The same thing 
can occur when, from other causes, perfect binocular vision has never existed, 
—as, for instance, in high degrees of myopia with almost similar eyes, but 
so short-sighted that perfect binocular vision is impossible without arti¬ 
ficial aid. Even individuals with healthy eyes, but with ill-developed in¬ 
tellectual faculties, are frequently unable to say what or how they see. In 
such cases the examination can be rendered much easier by holding a colored 
glass before one eye until the patient is aware of the double images. In the 
majority of cases it is sufficient to have made the patient perceive the second 
image by means of a red glass. We therefore use it only at the com¬ 
mencement of the experiment, and sometimes to verify the patient’s answers. 

It is always advisable to watch the eyes of the person under examina¬ 
tion : in most cases they at first follow the object correctly, then at a certain 
distance one eye seems to stand still, as if it hesitated, and finally, when the 
object has approached still nearer, it turns outward. 

At this last moment, however, the punctum proximum has already been 
passed over. The maximum of convergence is attained when the hesitation 
and crossed diplopia begin. 

To define the range of accommodation , the fine openings of the dynamometer are used. 
These are gradually brought nearer the patient till they appear indistinct; the result is 
read off on the tape in dioptries instead of metre-angles, and the maximum of refraction 
in the place of maximum of convergence. When a person is emmetropic, the maximum 
of refraction of which he is capable is equal to the range of accommod*^\n. 

The same line of luminous points may he used in investigatinWBue^^atfwm existing 
between the converging , or motor, and the accommodative , or optica ffifflparatus of the ej^es. 
When convergence and accommodation harmonize, the patie,^^m see single and dis¬ 
tinctly the row of luminous points as such. If convergenffi&eNxt fault, the line will ap¬ 
pear double, the diplopia being crossed if there he insuffictena^yor homonymous if there he 
excess. Should there be a failure in the optical adapta^Tmrhe points will appear blurred. 

The circular aperture of the dynamometer is iKcfap^ the analysis of all kinds of de¬ 
rangements of motility which are accompanied fvy ra«pmpia. 

The case of the dynamometer also contaw^V little frame, with a handle, in which 
threads, hairs, small objects, such as printed lA&l’s, or a diaphragm with fine holes, can be 
placed to define the range of accommodat^j 

It lias been said above tJi^me maximum convergence is ou the aver¬ 
age 9 ma to lOma. As a nuN^Jof fact, we have rarely met insufficiency of 
this function among uePfe&uJ capable of converging to a point ten centi¬ 
metres distant. 

Such a case, hb^Jer, might be present if the individual were obliged 
to work binoci jjQp at a particularly short distance. Indeed, since, ac¬ 
cording to ^J^experience, two-thirds of the convergence must be kept 
in reserve^S^only one-third ought to be expended, the 9 ma would suffice, 
theoretically, only for a distance of thirty-three centimetres. Twenty-five 



would demand Sma in reserve, hence 12 ma altogether. 


4 $ 

It is not rare to find this amount of* converging power,—indeed, even more, 
especially in the case of persons who have trained themselves to it,—but 
any one who possesses only 10 ma as the maximum of convergence would 
soon tire himself out by working at a distance of a fourth of a metre. 

On the other hand, Sma of maximum convergence would not constitute 
of itself an absolute insufficiency of convergence. The individual need 
only move farther from him the object on which he is working, or fre¬ 
quently interrupt his work for the purpose of resting his muscles, and 
thus restore their exhausted power. But 8 ma seems to us a minimum below 
which convergence could scarcely fall without symptoms of asthenopia 
showing themselves. Under such circumstances the patient says that the 
first moments of work pass fairly well, but there soon comes a feeling of 
fatigue, more or less localized, accompanied by pain in the forehead, the 
temples, or the head generally. At the same time, vision becomes indis¬ 
tinct, from a cause which escapes most patients. However, those among 
them who have some ability as observers remark that the object of fixation 
becomes double ; for instance, they see the printed page separate itself into 
two images, which glide in opposite directions, one of the images under¬ 
going the apparent displacement, while the other continues stationary. At 
this moment, they have at times the distinct sensation that one of the eyes 
has deviated outward. 

A phenomenon which is frequently noticed by persons with insufficiency 
of convergence is a certain difficulty in successively directing the gaze from 
one to another of different near points whose distances vary~ These differ¬ 
ent successive fixations are not executed with the prompt^^and precision 
habitual to healthy eyes; the objects, before being fix^Mppear indistinct 
or double, and the movements of the eyes, of whk^JcJrmal eyes are not 
conscious, occasion a certain feeling of annoy an c«-v 

The momentary occlusion of the eyes, or^Mfre or less prolonged gaze 
into space, dissipates these symptoms, ai^H&^fion again becomes possible 
for a certain time; but the fatigue is toftwcd, becomes more intense, and 
necessitates a new interval of repos^^VFor a certain length of time it 
always causes marked fatigue. p 

In other cases, asthenopia ^mjreases to such a degree as to render all 
work impossible, or to piwd0$ af the end of a short time, intense cepha¬ 
lalgia, hemicrania, with ^^v^he concomitant train of symptoms, such as 
nausea, vertigo, etc. { 

A short objectiy(Examination sometimes suffices to recognize insuffi¬ 
ciency of convej^ftmS?. It is enough to make the patient look at an object, 
which is broug^Dgradually nearer to his eyes, along the median line. It 
can be s^^^wit at a moderate distance the movements of convergence are 
relaxed become undecided. The patient has a tendency to recoil, to 
with&sW from the object of fixation. If the latter be brought still nearer 
thc\^es, they commence to show oscillations, and at length entirely re- 
nce fixation and become divergent. This phenomenon manifests itself, 




Fig. 50. 

of course, only in one of them, which suddenly stops, then executes an asso¬ 
ciated movement outward, while its companion continues to turn inward. 

This is, after all, the same phe¬ 
nomenon that occurs, under normal 
circumstances, as soon as the object 
of fixation is brought nearer than the 
punctum proximum of convergence; 
only in the pathological condition it 
is produced earlier; indeed, even some¬ 
times during vision at great distance, 
when the maximum of convergence is 
zero or negative (7, Fig. 48). 

The insufficiency being thus recog¬ 
nized, and the maximum of conver¬ 
gence determined by means of the 
dynamometer, we measure also the 
negative part of this function by 
means of abducting prisms, or, more 
simply, with Herschel’s double prism 
(Fig. 50). 1 

This instrument, which the optician 
Cretes, of Paris, formerly made for 
the use of ophthalmologists, consists 
of two prisms of equal power which 
turn around the same axis in opposite 
directions. When the apices of the 
two are directed in exactly opposite 
directions, they neutralize each other, 
their surfaces being parallel. On the 
contrary, when the apices have the 
same direction their action is the sum < 
of the powers of both prisms. 

From one of these positions to^ 
other the double prism presents,! 
fore, all the degrees, from ^ze©j£<£^he 
sum of the two prisms oJ^%hich it is 
composed. S* 

The degrees of die resultant prism 
are engraved ojNlQ handle of the 
instrument, anAaJ’e indicated by the position of the knob, by pressure on 
which thaW^us are moved. 

Herschel’s double prism with Landolt’s 

1 -\Jp n venient arrangement for this purpose, devised by Noyes (Diseases of the Eye, 

S|^\isja i 

series of square prisms set one above another in a frame and increasing in 
tyer^y intervals of one degree of deviation. One series may have odd numbers up to 
degrees, and another even numbers up to eight degrees. 

^ a.--- !g.v- - ^.._- •••• . .^v. "- ^ • ' 


We have had substituted for these figures, which formerly indicated the 
angles of opening of the prisms, the more rational ones corresponding to 
the angle of deviation produced by the combined prisms. 

On the circular mounting of the instrument, we have had engraved the 
corresponding metre-angles for a base-line of fifty-eight millimetres (chil¬ 
dren), and for a base-line of sixty-four millimetres (adults). 

Nothing is easier, then, than to find the maximum of divergence and 
express it in metre-angles. One need only make the patient fix a distant 
candle-flame and turn before one of his eyes the prism held in such a way 
that the apex of the resultant prism shall be directed towards the temple 
of the same side. As soon as a homonymous diplopia commences to mani¬ 
fest itself, we know that we have reached the limit of divergence (—r), 
and we read the degree of it on the mounting of the instrument. 

By subtracting this amount from that of the maximum of convergence 
(p), we obtain the amplitude of this function, 

a — p — r. 

If acquaintance with the minimum of convergence be interesting even 
with reference to the nature of the insufficiency, it is still more so, as we 
shall see, when regarded from a therapeutic point of view. 

In order to complete our diagnosis and learn whether the power of con¬ 
vergence alone has changed, or whether there exists a weakness of the mus¬ 
cles themselves, we must examine the excursions of the eyes by means of the 
perimeter, according to the method which we have formerly described. 

Finally, the examination of the state of motility ma^be completed by 
the determination of the so-called position of equilibrium^6f the eyes. 

The term position of equilibrium is used to desigpQ£ the direction taken 
by the eyes when in a state of minimum innervatffl^or of absolute repose . 

Nothing is more difficult than to find this w«5toion. In fact, it could not 
be determined by any other means than $^p5e subjective method,—that 
is to say, by the aid of the indications fav&n by the person himself under 
examination. For it is not the directj^of the pupillary axes that is to be 
sought, but that of the visual liu£s. concerning which the patient is the 
sole judge. But any object of tfBjjyfvation, whether near or distant, influ¬ 
ences the direction of the^^Jtyes, even when it is seen only by one of 
them, and that not only tnyfene effort of accommodation which the vision 
of this object demand^bfu even by the distance at which the individual 
supposes the object 4o be, whether correctly or fallaciously. 

The eyes ara^^hobile, and the innervation of their motor apparatus 
is both so pqpfyex and so delicate, that even a semi-conscious thought 
suffices taN^J&ify their relative direction. It is modified even during 
dreams.. Nmy profound narcosis or death brings about the absolute re- 
laxatift\of the ocular muscles. But under such circumstances it might 
^ amen It to get an answer from the person consenting to undergo the 


In default of this absolute resolution of innervation, one seeks at least 
to withdraw the patient as much as possible from the influences capable of 
modifying the direction of his eyes. When the vision is concerned with 
very distant objects, the least possible demand is made upon the accommo¬ 
dation. On the other hand, the tendency to fusion is diminished by ren¬ 
dering dissimilar the images of the two eyes by means of a colored glass, 
and even more so by means of a prism which produces insurmountable 
vertical diplopia. 

In conducting this investigation, Stilling 1 makes the person under ex¬ 
amination close the eyes and then say whether a star or some other distant 
luminous object appears Single or double at the moment when the eyes are 
opened. Or, again, he makes the patient look at this luminous point and 
then successively covers and uncovers one of the eyes to learn if, in spite 
of the suppression of binocular vision, the excluded eye remains in paral¬ 
lelism with the other, or if it modifies its direction by converging, by di¬ 
verging, by upward or by downward deflection. 

Although the author has found in certain cases a homonymous diplopia 
by means of this proceeding, the notion of the great distance of the object 
fixed certainly suffices in other cases to prevent the eyes from converging 
under these circumstances. On the other hand, there must be also many 
persons who do not diverge, because no object which is fixed under ordinary 
conditions requires this direction of the visual lines. 

A method which Donders used to determine the condition of rest of 
the eyes appears to us preferable to that which we have just mentioned. 
The Dutch physiologist brought the person to be examingdTn^o an abso¬ 
lutely dark room. One of the eyes was covered with a ^^glass and the 
patient’s face directed towards one of the walls of t]\r\a^artment. At the 
end of a certain period of repose, an electric SD30> appeared before the 
patient. Single vision or the nature of the dM^pia in which this light 
appeared indicated the direction which thefey^iiad taken during the ab¬ 
sence of any object of fixation. This ex^nment has the advantage that 
the rapidity with which the luminous ^^eet appears and disappears does 
not permit the patient to modify the direction of his eyes according to the 
distance which he attributes to thd^Wect. 

Snellen uses in his clinic «A^&l*echt a very ingenious method for deter¬ 
mining the degree of di^efpihce or convergence of the eyes in what is 
at least a relative state ^flepose. This experiment also is made in an 
absolutely dark roopi^JThe patient has in front of him a great number of 
apertures made in arfe^rd and arranged as a horizontal line, covered with a 
red glass, and jl^njmated from behind ; below one of these holes is another 
covered witftwgreen glass. 

The person under examination wears spectacles of which one glass is 
red, entary to the green of the aperture of the board, and the other 




Vol. IV.—10 

1 Stilling, Arch. f. Augenlieilk., xv., 1, S. 73, 1885. 


green, complementary to the red covering of the line of apertures in the 
board. Hence the person sees with one eye only the red points, while the 
other perceives only the green point. Then the patient is asked to say 
whereabouts along the line of red points he sees the green one. The 
distance between the place where the green point actually is and the place 
where the patient supposes it to be is equal to the tangent of the angle of 
deviation. The latter can be read directly on the scale. 1 

A good method of determining the position of equilibrium or the latent 
deviation of the eyes is that of Maddox, which, under the name of rod- 
test , 2 is pretty generally known and appreciated. 

That author places before one of the eyes of the person to be examined 
a glass rod which is not more than two or three millimetres in diameter. 
Any luminous point looked at through this cylinder is changed into a long 
line of diffusion. The direction of this line is necessarily perpendicular to 
that of the rod. When looking thus towards a distant candle-flame, we 
receive from this object two entirely dissimilar images, on one side the 
normal one, and on the other the luminous line. The difference between 
this line and the image received by the free eye is still greater when one 
of them is reddened either by using a red rod or by covering one of the 
eyes with a glass of this color. It is evident that the rod must be opposite 
the pupil. To facilitate this position, Maddox now uses a series of parallel 
rods, so that the person under examination is always sure to look through 
at least one of them. Such a series of rods is mounted on a disk of metal 
of a size to fit into any ordinary trial frame. 

If it be a question of determining horizontal de^gti 
given an exactly horizontal direction, and the ligfeD appears to the eye 
before which the rods are placed, in the formeffSa vertical line. If the 
eyes are normally directed, this line passe^&^ctly through the candle- 
flame. Convergence will provoke homommQ)s diplopia, divergence crossed 
diplopia. For vertical deviations the r^js/ire held vertically, so as to pro¬ 
duce a horizontal line of light. 

The degree of this deviation ma>Jbe measured in different ways. Thus 
one may find a prism which^4©fluces fusion of the two images. If one 
uses for this purpose a da^rcsywism which has our graduation, one may 
obtain the degree of expressed at once in ordinary angles and in 

metre-angles. ^ O 

V.I11 a vi. 

nations, the rods are 



1 M. J. Rebfli^J^s used Snellen’s method in investigations concerning the direction 
at the eyes^fcjunder the influence of what he calls Vhabitude physiologique (physio- 
gieal ha^JtJS 

HeW^^ihat this direction is, in the majority of cases, parallelism or divergence (sixty- 
one pec* ceSt.). Convergence (thirty-nine per cent.) is met with when an effort of accom- 
modjAn is necessary in order to procure for the fixing eye distinct retinal images. 

. X j f f s evident that the results of these investigations constitute further confirmation of 
OUonders’s law concerning the relation between convergence and accommodation. 

2 E. Maddox, A New Test for Heterophoria, Ophthalmic Review, May, 1890. 


This deviation may also be measured by means of the mural division 
which I described many years ago, and have mentioned above. 1 

The different methods which Dr. George T. Stevens uses for the deter¬ 
mination of what he calls heterophoria are to be found in the article on 
the Estimation of the Balance of the Extra-Ocular Muscles, vol. ii. of the 
present work. 

Professor Straub, 2 of Amsterdam, recommends the following method 
for the determination of the position of repose of the eyes during vision at 
different distances: 

A ribbon, a metre and a half long, has at one of its ends an oblong 
mirror, and at the other end a wooden plate, large enough to cover one eye. 
The person under examination is seated with his back towards the window; 
the observer, sitting in front of him, holds the mirror horizontally in front 
of his own forehead and tells the patient to fix the image of some object 
reflected in the mirror. By rapidly and alternately covering the eyes of 
the patient, he ascertains if they have a tendency to be dissociated, and in 
what direction. 

Priestley Smith 3 very ingeniously remarks that the corneal reflex from 
an ophthalmoscope may serve to teach us the direction which the eyes have 
when deprived of binocular vision. Indeed, the ophthalmoscope mirror 
presents a luminous object of fixation to only one of the eyes of the person 
examined. Hence the other can, without prejudice, take the direction 
which is easiest for it,—a direction which its corneal reflex then reveals to 
the observer. \ 

Instead of diminishing the tendency to fusion of the bridges belonging 
to the two eyes by making them dissimilar, as Maddaxf^tevens, Snellen, 
and others do, this fusion may be rendered impossible kjrthe aid of a very 
simple method devised by von Graefe. This con&i(^iin placing before one 
of the eyes a vertical prism. The person exgmtfrraf then sees, for instance, 
a candle-flame with a vertical diplopia whichuie\ahnot overcome; he is thus 
brought to abandon his eyes to their direction of relative repose. If this 
direction be parallelism, the two image^pli appear to be in the same ver¬ 
tical line. In addition to the diffei^0p in height between the two images, 
convergence will show itself by hopjjjgymous diplopia, divergence by crossed 
diplopia. The degree of th^e deviations may be measured by means of 
our tangential division, oal0tl he prism which brings the two images into 
the same vertical line. 4 \ 

d’Ocul., 1875. 

. for the determination of convergence power and the position 

1 Landolt, Strabon 

2 Straub, An inglmjent 1 

of rest of the e^^jophthalmie Review, April, 1802. 

3 Smith, corneal reflex as a test of fixation and deviation, Ophthalmic Review, 

February, 1£9^V 

1 Se^llb J. F. Herbert, A scale for the speedy and accurate determination of the 
anomalrl^f fhe ocular muscles, Ophthalmic Record, p. 324, 1894. The author uses a scale 
whip^s not divided into angles, but into prism-dioptries , according to the proposal of 

•Vi. : 

U- > S; 


Used in this way,—that is to say, with the fixation-object at a great 
distance,—this method of our eminent master may help to elucidate the 
complex problem of the motility of the eyes. We dare not say as much 
concerning its application for short distance, for which von Graefe used it, 
in determining what he called insufficiency of the internal recti muscles. 

This method, which the great Berlin ophthalmologist called “Gleichge- 
tmhtsvermeh” is, however, still so much in use that we cannot pass it in 
silence. It is employed at the distance of near-work,— i.e., at about thirty 

In front of one of the eyes is placed a vertical prism of about six 
degrees, which produces a vertical diplopia of the object of fixation. This 
object consists of a black point through which passes a vertical line. If 
the two vertical lines do not join, but are separated from each other, the 
horizontal prism which superposes one on the other is sought. 

In the case of crossed diplopia, the prism thus found ought, according to 
von Graefe, to give the amount of insufficiency of convergence. 

Yon Graefe attached, moreover, great importance to the measurement 
of what he called the abducting power, or simply abduction, at working 
distance, as well as at a distance of several metres. 

Abduction at a great distance is nothing else than potential divergence 
of the lines of sight, or what we call the negative portion of the amplitude 

of convergence. 

To the same extent that investigation of absolute divergence is rational 
and useful, so is the opposite attempt (by means of ^Jducting prisms) 
devoid of sense, utility, and accuracy. 

The criticism of this proceeding is to be fouqKhi our work on the 
movements of the eyes and their anomalies. 2 s * ia ^ not renew * ts dis- 

cussion now; it is easy to see that von Graelfc(A$vestigation could not give 
useful results. By obliging the person ex^Med to change his convergence 
(or divergence) without changing Ids Accommodation,—since the distance 
of the object remained the same,-^ placed him in conditions of vision 
which were entirely abnormal. W 

However interesting thes^X^vestigations concerning the position of 
equilibrium and latent deviap Q>of the eyes may be, they in no wise suffice 

R^ptitude of the eyes for work or of the nature 

vv kj 1.1 ava vjnit^wrong, for instance, to conclude, from the existence 
of what has b^fijcalled “ latent divergence,” that insufficiency of conver¬ 
gence was* pr^sarft. Eyes in the condition of absolute repose may diverge, 
the equ^Wlnbm test may indicate a distinct crossed diplopia, while never- 
thelesIsSi^power of convergence may be perfect. Study of the position of 
eq ^bnum teaches us, at the utmost, the tendency of the eyes to diverge 

to inform us either of 
of the asthenopia. /■* 
It would be q 

i Von Graefe, Arch. f. Ophth., viii. 2, 1862. 

3 De Wecker et Landolt, Traite complet d’Opht., iii. pp. 912—915. 


Fig. 51. 

or converge, the direction which they would probably take if binocular 
vision were lost. It is, like the 
measurement of abduction, a guide 
in our therapeutic undertakings. 

A more instructive test is to ob¬ 
serve the eyes during fixation, and 
especially during near-work. We 
have devised for this purpose a most 
simple instrument. 1 It consists of a 
glass plate, framed, and mounted on 
a handle. (Fig. 51.) 

On this glass we fix bits of print 
or figures of all sorts. We hold it 
at the desired distance between our 
eyes and the patient’s, and, while he 
fixes, reads, or follows the test-objects, 
we observe his eyes through the glass. 

This instrument may be called a 
“ kinophthalmoscope,” from xbrjecs 
(motion). It has served us in our 
investigations concerning the physi¬ 
ology of the movements of the eyes 
(Arch. (VOpht , 1891, p. 385) by 
showing that, even in a normal condition, the eyes move bv jumps and 
not continuously. 

Landolt’s kinophthalmoscope. 



uY : 

A s 


Insufficiency of convergence and divergent sfei^bismus are so intimately 
related to each other, and the lines of procec/Tim^n the two conditions are 
so similar, that we may consistently combfmrin the same article the treat¬ 
ment of both affections. 

It is self-evident that this treatment will be, first of all, etiological . It 
is true that when the divergence i^jJue to a cerebral lesion our therapeutic 
resources are often very limit^tL(2> ^ 

In tabes the paralysis frfvbonvergence, as well as that of the ocular 
muscles, is sometimes se®Ttraisappcar spontaneously. 

Hysteria and neurmtfienia are more accessible to medical intervention. 
This is not the place^Tliscuss in detail the multiple means which may be 
employed in tl}cM?s^mnplex affections. The essentials will always be physi¬ 
cal, intellectmoral hygiene, a rational and comforting regimen, out- 
of-door e^rcisk, good nourishment, and the like. Hydrotherapy, judi- 
ciouslviaSMied, almost always does patients of this kind much good. It is 


1 Landolt, Soc. frai^aise d’Opht., 1892, p. 253. 


often advisable to remove them from their ordinary environment, to make 
them travel, or, at least, change their residence. Other surroundings give 
rise to other ideas; from calm mountain heights, the annoyances, cares, and 
ambitions of a busy life appear small or disappear altogether, like the 
human habitations one has left behind, and which are scarcely perceptible 
below one’s feet. Considered from the other side of the ocean, a question 
may change its aspect, and often shows us its better side. 

These considerations are of special importance in the case of asthenopes 
whose malady is due to overwork. It is for them especially, that repose of 
the mind and of the eyes, as well as change of habitat, hydrotherapy, etc., 
have the best influence. 

Evidently these good influences can do no harm to those whose insuffi¬ 
ciency of convergence is due to a lack of use of their adductor muscles, 
though they will not effect a cure. It is the exercise of the impotent func¬ 
tion more than anything else which will render them service. 

In this connection it seems appropriate to attempt an explanation of the 
difference of opinion among equally competent authors. Some of them, as 
Noyes, for instance, recommend these exercises in insufficiency of conver¬ 
gence and incipient divergent strabismus. 1 Others, like von Graefe, advise 
the opposite, saying that the efforts required of the adductor muscles would 
only fatigue them and weaken them still more. 

To us it seems that in different conditions each opinion may be correct. 
Thus, von Graefe is certainly right for many cases of our first and second 
forms of insufficiency. On the other hand, proper excises may be in¬ 
dicated in cases of the third form, where the infirn^tfVis* ascribable to a 
lack of exercise, and, moreover, in cases where, surgical interven¬ 

tion, the adductor muscles are prepared to resun^MyW function. 

When there is only insufficiency, these era^c^es may be performed with 
a clear, small object, a black spot on ay^^background, or, better still, 
with the luminous aperture of our dynamometer. This object of fixation 
is gradually brought nearer the patie^s eyes along the median line, or, what 
amounts to the same thing, the pat^j)t approaches the object, taking care to 
overcome as long as possible tl0^endency to double vision, which becomes 
increasingly manifest as tW^^-object approaches the punctum proximum 
of convergence. It issfofeSsely for the sake of rendering this diplopia 
clearer, and, on th^tl^eVhand, to aid fusion, that it is best to choose as a 
fixation-object, notV^Jinger or a pencil, but a very fine luminous point or 
luminous line* 

In the commencing divergent strabismus , exercise of this sort may 

still be of^eN?ice, but only on one condition,—that is, that binocular vision 
existOOIJfcnce high degrees of strabismus and cases in which one of the 
eyestis markedly amblyopic or amaurotic are from the outset excluded. 

binocular vision is lacking, but the sight of both eyes is fairly good, 

Compare, likewise, R. Cross, Asthenopia, Bristol Med.-Chir. Journal, p. 181, 1893. 



the treatment should begin by stereoscopic exercises for the purpose of re¬ 
establishing fusion of the retinal images. The stereoscopic objects, at first 
widely separated from each other, are gradually brought nearer, with the 
view of bringing the eyes towards parallelism and thence to increasing con¬ 
vergence. We follow here the converse principle from that which guided us 
in the treatment of convergent strabismus. In that case, we took care to 
exclude, by means of the strongest convex glasses, any effort of accommo¬ 
dation, for the sake of diminishing at the same time the impulse to conver¬ 
gence. Here, on the contrary, we give the patient the weakest convex 
glasses with which he can still distinguish clearly the stereoscopic objects, 
and we diminish their strength in proportion as, by the diminution of the 
distance between the objects, the convergence increases. 

There may even present itself a case of so high a degree of myopia that 
the patient does not need glasses, or even needs concave glasses, in order to 
see distinctly to the bottom of our stereoscope. In such a case, an increase 
in the power of the concave glasses will stimulate his convergence. 

I beg permission to cite here an observation well adapted to demonstrate the utility 
of such exercises. I noticed one day in the waiting-room of my clinic a woman whose 
divergent strabismus was striking at the first glance. I had no doubt that it was with 
reference to this infirmity, that she had come, but she declared that her visit was only to 
bring her child, suffering from an ophthalmia; that, as for herself, she had squinted too 
long to think of seeking treatment for it, and that she did not desire it. However, I got 
permission to examine her. 

I found, in the left eye, myopia 0.25 D., V = 1, and in the right eye, myopia 0.5 D , 
V =r0.9. The latter eye diverged through an angle of thirty-nine degrees; the fields of 
fixation of the two eyes did not exceed thirty-five degrees to the nasal the temporal 

side was also of less extent than in the normal condition. 

On making the patient look at a distant candle-flame, she di^J^t see double, either 
with or without a colored glass, but crossed diplopia appeared^v^eh a vertical prism was 
placed before one of her eyes. Hence there was suppression^Kthe impression received by 
one of the retinae in the horizontal meridian, the parts abo^Jla below having maintained 
their relations with the retina of the other eye. 

The patient being emphatically requested to f^£^iear object, she made a few efforts 
of convergence, but the eyes were far from acmmrng the proper direction, and the right 
eye again resumed at the end of an instant its faj^ergence. Nevertheless, we encouraged 
the patient to undertake stereoscopic exercise^ 

She acted on this advice, but with<|E?0&meh enthusiasm. It was rather with a view 
to please us, that she looked into the at^^^pope, while present for the sake of her child’s 
treatment. In spite of that, w^^K^eeded in re-establishing binocular vision and in 
achieving a complete disappe^ra^?Oof the strabismus at the end of two months. The 
normal condition persisted ifcr several months,—that is to say, so long as the patient con¬ 
tinued occasionally the stereoscopic training. She negligently abandoned it, not caring, 
as she had declared at fiufr^tset, to be cured. But, for our part, there exists no doubt that 
this person would ha/(\afchieved a perfect cure of her strabismus if she had continued 
the stereoscopic♦tJi^jTg regularly, and had substituted for it later direct exercise of the 

However this may be, the result proves that, even in the case of a divergent strabis¬ 
mus of IqjA standing and of high degree, orthoptic training may have a very favorable 
influeA^N TJiere is all the more reason why such training should exert a beneficial influ- 
enc^jyhefi strabismus is beginning, and especially in insufficiency when due to a lack of 

K 1 


Fig. 62. 


Such training may also be undertaken in certain cases of muscular 
insufficiency. But in most instances it is better to cause the orthoptic ex¬ 
ercises in such circumstances to be preceded by a more radical and powerful 
remedy, that is to say, by operation, of which we shall speak later. 

All these treatments, general and orthoptic, even under the most favor¬ 
able circumstances, demand much time. Hence it has been sought to solace 
the victim of asthenopia or insufficiency of convergence by means of pal¬ 
liatives until his infirmity shall have disappeared. In short, it has been 
sought to diminish the convergence required for his work. 

Evidently, the simplest means of achieving this is to inet'ease the dis¬ 
tance between the eyes and the fixation-object. This is so easily done, indeed, 
that most asthenopes are found to have naturally adopted it even before 
they consult us. It is only myopes, whose punctum remotum is situated 
very near their eyes, that we can sometimes relieve with concave glasses, 
which, by increasing the extent of their vision, permit them to read and 
write with less convergence. 

Thus, the myope of 4 D. is obliged to make an effort of convergence 

of 4 ma in order to work at the distance of 
his punctum remotum. And, as the experi¬ 
ments above mentioned have taught us, he 
needs twice as much as this,—that is to 
say, 8ma, in reserve, or a total of 12 ma of 
convergence power. By giving him con¬ 
cave glasses of 1 D., we\carry his distinct 

vision to Th|^gfore we have di¬ 

minished by oi^Nptetre-angle the conver¬ 
gence necesja^ior fixation, and by 3 ma 
the total M0yfred for continued labor. 

Bui jMfctice proves that the applica- 
bili^HConcave glasses for this purpose is 
delimited. If the degree of the myopia 
high, the glasses necessary to lessen effec- 
^ ,tively the convergence are so strong that 
the reduction which they produce in the 
size of the retinal images becomes a new 
cause of fatigue to the patient. 

Hence attempts have been made to di¬ 
minish the ^^ergence by other optical appliances,—that is to say, by 

iCj^vl^lace in front of one eye or in front of each of them a prism 
whoceapex is directed towards the temple, as is shown in Fig. 52, rays 
^5^ing from the distant object 0, instead of continuing their course in a 
Vsffaight line towards o, will deviate at P, towards the base of the prism, 
^4 the direction Pf. The eyes, instead of being directed in a parallel direc- 


tion towards 0, during distant vision, will be directed towards D, that is 
to say, they will diverge through an angle equal to twice the angle DPO . 
It is for this reason that the name abducting is given to the prisms placed 
with the apex towards the temple. 

If the object be brought nearer, the convergence required for its fixation 
will always be less by this angle than it would if the individual were not 
using these glasses. 1 

It is evident that, if the patient also require concave or convex spherical 
or cylindrical lenses, the two surfaces of the prism may be utilized for this 
purpose. Thus it becomes possible to combine the two optical appliances 
before mentioned for the diminution of convergence,—concave lenses to in¬ 
crease the distance of the punctum remotum , and prisms to modify the direc¬ 
tion of the visual lines. 

For the same purpose, spherical lenses may be decentred ; that is to say, 
they may be placed before the eyes in such a way as to use an eccentric 
part, which has the same effect as the prism combined with a spherical 

Fig. 53. 

o o 

, in Fig. 53, inst eMM cutting the concave spectacle glass with its 
)incident with JjjfS^tical centre of the lens,—that is to say, along 


centre coincident 

AAA A ,—it may be ^uj^ from an eccentric portion, along BBBB. The 
luminous rays ccan|j)^ from 0 are then deviated at P towards the base of 
the prisms thus/C^feained,—that is to say, towards /. In this way, the eyes 
that use tl*es^g!asses are obliged to diverge (/P) when looking at a great 
distance or to converge less when looking at near objects. 

To t>btkin the same effect with convex glasses, the patient must be made, 


o oot 

insult in this connection the treatise of Maddox, The Clinical Use of Prisms, 
ol and London, 1893, and Prentice, vol. ii. of the present work. 


on the contrary, to look through the outer part; the glass should be cut, as 
is shown in Fig. 54, so that the centre of the glass when mounted in a frame 
will be farther out than is its optical centre (BBBB instead of AAAA). 
Here, again, the convergence is diminished for each eye to the extent of the 
angle oPf. 

Great hopes were entertained as to the efficacy of prisms in the treat¬ 
ment of motor asthenopia. These have not been entirely realized, for 
reasons which our calculations explain. WVj 

Indeed, we have seen that a metre-angle corresponrapo a prism of 1° 
40' (No. 3J, according to the old numeration) place(^Q$Sre each eye. This 
is about the limit of the prism that can be useepp practice. Otherwise 
the glasses are not only too heavy, but the ol&uaiatic aberration and the 
deformity of objects which they produce b/c&ra^too troublesome. 

The aid that can be given to a p^derMby means of prismatic glasses 
is therefore scarcely a metre-angle a^0 a half. The effect of decentring 
lenses is often still less. Now, th@4nsufficiency which gives rise to asthe¬ 
nopia is generally due to a defertN^the convergence power much greater 
than one or two metre-angksj0j ** 

We do not deny the^wjKty of prismatic glasses, or of decentring in 
low grades of insuffici^urg^Dut in high degrees they have no value. In the 
former case it is even elSential to guard one’s self from judging by appear- 
unces, as thesec^yiSlen get well of themselves. 

I may^umS^here an observation well lit to instruct us concerning the efficacy of 
prisms in mrebopia. On examining one day the spectacles of a patient who had come 
to consul^ m^for something different from asthenopia, I found that she had been wearing 
bins with their ajjices towards the nose. These spectacles, she told me, had been 


Landolt, Insufficiency of the Power of Convergence, Ophth. Rev., p. 190, 1886. 


prescribed for her many years before by Dr. L., and they were absolutely indispensable 
for work. 

At my request the patient found the formula for her glasses, in which prisms were 
prescribed, but their apices were to have been in the opposite direction,—that is to say, 
towards the temples. The master, for he was one of the most competent of ophthalmolo¬ 
gists, who had prescribed the glasses had therefore hoped in this way to correct an in¬ 
sufficiency of the internal recti , as it was called in those days. But the optician had made 
a mistake, had mounted them in the opposite direction, and the patient had worn them 
and found them so satisfactory that she affirmed her inability to work in comfort without 
them. What is the conclusion to be drawn from this tale? Is it that, the doctor having 
mistaken an insufficiency of divergence for an insufficiency of convergence, the patient's 
guardian angel had so controlled the hands of the optician that the latter, by making a 
counterbalancing mistake, had set things in order? For my part, I see no other conclu¬ 
sion than the slight effect of weak prisms and the great power of imagination. 

If rest and general treatment are shown to be ineffective in insuffi¬ 
ciency of convergence, and if it be of too high a grade to be susceptible of 
correction by optical means, one is justified in having recourse to surgical 
intervention in order to re-establish the lost power. 

From the days of von Graefe’s to our own, tenotomy has been the usual 
operative procedure for remedying asthenopia. In insufficiency of con¬ 
vergence, the external recti are divided, for the purpose of diminishing the 
work of the adductor muscles by weakening their antagonists. 

The harm that has been done by these tenotomies is considerable. Not 
only has asthenopia very rarely been cured in this way, but a most trouble¬ 
some convergent strabismus, with homonymous diplopia, has often been 
added to the former trouble. 

In the surgical treatment of insufficiency of convergje^^fwo operations 
should be taken into consideration: tenotomy of thywductors and ad¬ 
vancement of the adductors. 

The former operation diminishes the powej*>«ndivergence, the latter 
increases the power of convergence. The fiA^f* these two operations is 
the simpler. But to know whether it is^TpSlrfable, we must first ascertain 
if the patient possesses divergence strong enough to allow a part to be sacri¬ 
ficed in the interest of convergence. such a case as is represented by 

the letters F and G of our diagrawp ^Fig. 48) we diminish by a tenotomy 
the already defective divergenc£^j$re minimum of convergence is rendered 
positive; in other words, a^0^ T e^ent strabismus is produced. 

Hence it follows thawWtotomy is out of the question in cases wherein 
divergence is zero ortfesytnan the normal. This is, as has been said before, 
very common. ^ 

If the diveragura be normal, as in D (Fig. 48), or exaggerated, as in 

That .dqb^ids upon what can be accomplished by i 
the diver^nce without the sacrifice of all this functi< 
the cternit of convergence, then teuotomy of one or l: 

na^Je indicated. But if it is not sufficient, then thi 
2^nts useless : asthenopia would persist in spite of it. 

qj^nce without the sacrifice of all this function suffices to supply 
;it of convergence, then tenotomy of one or both of the abductors 
indicated. But if it is not sufficient, then this operation is at all 

ts upon what can be accomplished by it. If diminution of 

vs be done ? 


Experience only can solve the problem of the efficacy of tenotomy. It 

has in our hands given the following results : When the conditions of the 

motility of the eyes are otherwise good, the excursions about normal, the 
amplitude of convergence only slightly limited, being, as it were, displaced 
towards the negative, as in B and C (Fig. 48), then tenotomy gives good 
results; that is to say, a partial limitation of divergence may increase con¬ 
vergence to the required amount. 

Let there be, however, no mistake: The tenotomy of which I am 
speaking, and which I consider as admissible in certain cases of insufficiency 
of convergence, although involving the entire extent of the muscle’s inser¬ 
tion, ought to be a simple tenotomy , limited to the strict detachment of the 
tendon from the globe, but not a setting bach of the muscle, as is obtained 
by disengaging the muscle from the surrounding tissues. In the latter way 
one markedly diminishes the excursion of the eye towards the side of the 
operated muscle. 

This fact is capable of the following explanation. Tenotomy thus prac¬ 
tised does not act so much by the displacement of the insertion of the 
muscle as by the weakening of its action. Indeed, the new attachment of 
the muscle to the ocular globe is usually not so firm as its original insertion. 
It takes place by the intermediation of a more or less lax cicatricial tissue, 
which holds the muscle in place relatively to its surroundings, but sensibly 
changes its influence upon the eyeball. 

Lot us cite 


ie before the operation. It is to he analyze^H^ 
rZ 7 - s } a - 10ma - K Cr 

ie before the operation. It is to he analyze^H^ 

rZ 7 - s } a - 10ma - K Cr 

Fig. 55. 


lidNof the fields of excursion—shows an insufficient development or great 
^ikness of the motor system of the eyes. In this case the sacrifice of a 



great part—even of the whole—of the divergence increases the positive 
convergence only very slightly. The amplitude of convergence remains 
reduced, and to the insufficiency of convergence which persists, is added an 
insufficiency of divergence, or, more correctly speaking, convergent stra¬ 
bismus with most troublesome homonymous diplopia. The patient sees 
double during either near or distant vision; the operation which was to 
have cured him has greatly aggravated his condition. 

It is to escape this danger that we generally abstain from performing 
tenotomy for the cure of motor asthenopia. Loyal to our principle of 
increasing the power of the iveak muscles rather than decreasing that of their 
antagonists , we have for many years had recourse in such cases to the 
advancement of the internal rectus of one of the eyes. Double advance¬ 
ment is only exceptionally necessary. We have found, indeed, that by mus¬ 
cular advancement much more is gained on the positive side of the amplitude 
of convergence than is gained by tenotomy , while nothing is lost on the negative 

Let us cite in support of this the following observation : 

Fig. 56. 

A boy ten years old, slightly myopic and astigmatic to 0.75 D., 
but having excellent visual acuity in both eyes. 

Asthenopia which has lasted a long time, in spite of glasses, 
general and local care, which the best physicians and specialists of 
this country have given him in profusion. 

His amplitude of convergence analyzes as follows: 

p _ 3.2o \ a __ 4 25 ma . It is shown in left vertical line of Fig. 56. 

r = 1 j 

Energetic advancement of one of the internal recti. 

Three weeks later the amplitude of convergence was found 

p — more than 20 ma. j n other words, the advancement ^>Q^red 
r— —1.5 ma 

for him a converging power much stronger even thaA^*®J normal, 
and left his divergence intact (right vertical line, 

This result has remained permanent. The yotng\n»i has finished 
his studies brilliantly, and when I saw him fkiru*Sn years later, his 
amplitude of convergence was still as extens^^> 



8 . . 



I so 

We could cite a number of^ufte as conclusive obser¬ 
vations as this, proving Tiority of advancement 

over tenotomy in motor asH^uopia. 

It is self-evident /tTat in deciding to intervene surgi¬ 
cally in a case of insufficiency of convergence we do not 
renounce the otMOjurative means which have already 
been discusseiAwe always consider them as indispensable auxiliaries with 
which to <^^^ve a complete and lasting cure. 





e principles which we follow in the treatment of divergent strabismus 
the same as those that have guided us in that of insufficiency of con- 


vergence. We shall only apply them with more energy. Thus, one will 
not hesitate long about intervening surgically. The best operation here 
also is muscular advancement, and it should generally be performed on both 

When the strabismus is of high degree and of long standing, especially 
when it occurs in an amblyopic eye, it will be best to practise at one sitting 
the advancement of both internal recti, combined with the resection of their 
tendinous extremities. If after weeks or months the effect of this operation 
should still be insufficient, the moderate tenotomy of one external rectus, 
or even of both external recti, may be added. But this is necessary only 
in extreme cases of divergent strabismus. 

After every muscular advancement we always bandage both eyes and 
keep them thus for at least five days, in order by their immobility to favor 
the attachment of the muscle. 

In convergent strabismus this suppression of vision by bandaging is 
very useful, for it diminishes the tendency to convergence, which might 
thwart the effect of the operation. In divergent strabismus the efforts of 
convergence are, on the contrary, favorable, inasmuch as they tend to the 
same end as does the operation,—that is to say, to the diminution of diver¬ 
gence. For this reason we leave off the binocular bandage in this case 
sooner than after an operation for convergent strabismus. After the re¬ 
moval of the bandage orthoptic exercises are immediately instituted. They 
tend, at first, to re-establish binocular fusion by means of stereoscopic ex¬ 
ercises. Then the patient is taught to bring a small luminpH^object slowly 
towards his eyes, just as in the orthoptic treatment of um^fficfency of con¬ 

If the operation should have accomplished ta|Qfeuch, which happens 
very rarely and only when the advancement ofktho internns has been com¬ 
bined with tenotomy of the externus, the set^sQj? muscle must be advanced 
by means of one or two sutures. - 

Unfortunately, one often sees operates even yet try to correct divergent 
strabismus by tenotomies alone. Thoj^are, generally, obliged not only to 
do what I have called exaggeratqCpfctting back of the muscle,—that is to 
say, to detach the muscle from its' connections with surrounding tissues,— 
but also to repeat this onMttRni several times. Many of them have re¬ 
course to what Graefe/mfQl a thread-operation, which consists in drawing 
the eye forcibly by rh^As of a suture towards the nose, with a view to 
obtaining an insertfejj of the external rectus still farther back. We again 
repeat what we(£mblished twenty years ago and what we have just said in 
discussino-^U^Speration for convergent strabismus, that this procedure ~ 
unwortHv ojvmodern ocular surgery. If one succeeds in thus giving 
the eyAs a parallel direction when they are directed straight forward, one 
jin insufficiency of the abductors, a convergent strabismus with 
onymous diplopia when binocular vision exists, in the lateral excursions, 
e eve has been partially removed from its muscular funnel instead of 




being put into it, as is done by advancement, or instead of being turned in 
it, as by advancement combined with tenotomy. 

I have published in the Archives di Ophtalmologie (March and December, 1895, and 
July, 1896) a series of characteristic observations concerning the various methods of oper¬ 
ation in the different forms of strabismus. May I be allowed to end this paragraph with 
a case that occurred to me while I was correcting the proofs of this work ? It concerns a 
man twenty-two years of age. His left eye showed: H. 0.5; V — 1; the right eye, M. 
2.5 with AS. m. 1.5; Y — 0.3. 

From the first years of life he was affected with a divergent strabismus of his right 
eye, amounting to 26°. 

The temporal excursions of both eyes were very extended (65°), the nasal ones notably 
limited (43° on the left, 40° on the right eye). 

There was neither simultaneous vision nor diplopia, nor, of course, macular fusion. 

I performed at once the advancement of both internal recti muscles with the resection 
of their tendinous extremities. 

Six days after, the sutures were removed. The seventh day, visual exercises were 
begun with a distant candle-flame, the left eye being provided with a colored glass, the 
right with its correcting lens. 

After a short time the patient manifested a crossed diplopia of 2°. With a prism of 
2° he saw the two images at the same place, hut without fusing them as yet. The same 
thing happened with the stereoscope: the two engravings were seen at first only simul¬ 
taneously, hut after some exercises the patient fused them in such a way that he per¬ 
ceived distinctly the perspective,—i.e., the relief. 

In Hering’s test with the falling halls, all his answers were correct. 

Continuing regularly the stereoscopic exercises, the patient recovered thus a perfect 
binocular vision and, with it, the ideal cure of his strabismus. 

Three weeks after the operation the maximum of convergence (p) was more than 
20 ma f the minimum —1.5 ma, therefore the amplitude of convergence \fcis 21.5 ma. 

This fact is extremely significant. It shows that the advanqgH^5™>f the abducting 
muscles has given the patient a converging power which considyh^y surpasses the nor¬ 
mal one, and that without damage to the abduction , which is eqy^feluperior to the normal. 

In the same way, far from losing, as after setting bad^pmewhat of the associated 
lateral movements, he has gained by the advancemenl^oj^^e muscles. The nasal excur¬ 
sions are now equal to 50° (instead of 43° and 40°)^?^tt6t the temporal ones pass still 
beyond 60°, as before. 



Leaving out of consideration ^ elevation of an eye which is strongly 
deviated inward, and the low™ which often accompanies high degrees 
of divergence, manifest strabismus is very rare. Generally, stra¬ 

bismus sursum or deoj^irfrlCVergens is due to the paresis or paralysis of a 
depressor or levator ^m»Ie, or to congenital absence of the muscle (Law- 
ford). A badly Deformed strabotomy may likewise give rise to a differ¬ 
ence in level befrwe&n the eyes. 

But verjti^K9cviations may exist in a latent condition. 

Dr. (ftmT, Stevens has especially drawn attention to this form of 
motor troubles of the eyes and to their consequences. We would refer our 
rea^ps to the chapter of this work in which that author himself has given 
tile results of his investigations. We here limit ourselves to saying that 
nt vertical strabismus shows itself especially by asthenopia. It is de- 


tected by the procedures which serve to make known the so-called “ direction 

of repose” or “ equilibrium” of the eyes. 

In order to measure the degree, the examiner provokes, by means of 
strong abducting prisms, a homonymous diplopia which the patient is in¬ 
capable of overcoming. Binocular vision being thus rendered impossible, 
the eyes promptly abandon themselves to the difference in height, the natu¬ 
ral correction of which has caused so much pain. The vertical diplopia 
serves to determine the degree of the deviation in height, according to the 
methods which have been described above. That is to say, the prism which, 
placed vertically before one of the eyes, brings the two images to the same 
level measures the degree of the strabismus. 

Let it be said, parenthetically, that one readily sees here how much more rational it is 
to express the action of the prism by the angle of the deviation which it produces than by 
metre-angles. The metre-angle , which measures the degree of convergence or divergence 
between two eyes separated by a base-line, has no raison d'etre when it is a question of 
elevation or lowering, in which case the two eyes may be considered as united by their 
centres of rotation. 

It is, of course, indispensable that the edges of the abducting prisms 
should be exactly vertical, and the edge of the measuring prism, as well as 
the line joining the centres of rotation of the eyes, exactly horizontal; other¬ 
wise one incurs the risk of provoking a vertical diplopia in healthy sub¬ 
jects, or of correcting it in cases where it exists. 

Vertical strabismus never attains as high a degree as convergent 
or divergent strabismus. Hence one often succeeds cting it by 

means of vertical prisms. It is well to divide the prafi&tic effect between 
the two eyes, turning the two apices in opposite diremons. 

If the defect require a stronger prism than three degrees, opera¬ 

tion is generally necessary in order to corm^l^^ If the ocular excursions 
are good and are equal in both eyes, the! of the superior rectus of the 

higher eye often suffices to remedy the aMienopia created by the strabismus. 

But it is nowhere more importantMftan here to take into account the 
counsel of prude 

tenotomy. A slightly felt s< 
muscle, even though perfi§ul 

direction of vision, ma^^gjl 
the eyes move toward^JjJe s] 
for this reason thafi^if a te 


form it on the ltfratar rather than on the depressor. This is because, the 
eyes being^dQsoiten used in looking downward , insufficiency of a levator 
is less trs^B^ome than is that of a depressor. 

If bheaiflference in height is very marked, and especially when exami- 
nabtaNcuJ the excursions demonstrates a gap in the lower part of the field 
c&^x5tion of one of the eyes, we perform the advancement of the infenor 
fpdus of this eye, according to the principles already explained. 


Vertical strabismus is generally mucE more rebellious to treatment than 
horizontal, and in the higher degrees one may be obliged to operate on both 
eyes in order to remedy a strabismus sursum or deorsum vergens. 

Our method of procedure for correcting a difference in height between 
the eyes may be summed up as follows: 

The eyes being generally employed in looking downward, it is better to 
lower the more elevated eye than to elevate the lower one. This lowering 
may be obtained in small degrees by tenotomy of the superior, but it is 
usually preferable to advance the inferior rectus. In the highest degrees 
the combination of advancement with tenotomy may become necessary. 

It will be noticed that I operate only on the recti muscles. In fact, 
though I was the first to perform the section of an oblique muscle ,—that of 
the inferior at its origin, 1 —I am far from advising this operation with a 
view to remedy, for instance, paresis of the inferior rectus of the other eye, 
notwithstanding the fact that this oblique is the antagonist of that rectus. 
We perform the section of the inferior oblique only in the very rare case 
in which we desire to bring to the middle of the palpebral opening the 
upper part of the cornea, when it alone has remained transparent and has 
had an artificial pupil made opposite it. The combination of all the means 
at our disposal—tenotomy of both levators and advancement of the inferior 
rectus—may then be necessary in order to obtain as considerable a lowering 
of the eye as is requisite. 

It is unnecessary to add that here, as in all strabotomy, xjareful watch¬ 
ing of the patient, binocular bandaging, etc., are essential .a^Hliat orthoptic 
training will aid us in controlling and confirming thg^ewct of our oper- 


Nystagmus consists of an oscillatory , irwStiwitary, rhythmic movement 
of the eyeball , having small range , and bei&glw&e or less continuous. This 
movement may take place in the horizorfo,] otrection ( horizontal nystagmus), 
in the vertical ( vertical nystagmus), or ^y represent a more or less extended 
rotation around the line of sight {(ftary nystagmus). Sometimes it affects 
the direction intermediate betw^kUie horizontal and the vertical {oblique 
nystagmus). Finally, the < Ins of the globe, while remaining rhyth¬ 

mic, may simultaneously »™tekent different types of ocular movements, in 
which case the nystagmuses called mixed. 

Nystagmus is generally binocular and associated, at times it is uni¬ 
lateral. In the laiter case it is almost always vertical. 

In nyst^g^MSf properly so called, the rhythmic oscillations are pro¬ 
duced in 4 ^^h’ections of vision. Their range and rapidity, however, 
vary underlie influence of certain causes. They stop during sleep; they 
are pronounced when the victim of them is aware that he is being 

* Landolt, La tenotomie de l’oblique inferieur, Arch. d’Opht., 1885, p. 402. 

( 2 See Landolt and Eperon, loc. cit., p. 932. 

✓ Vol. IV.—11 


watched than when this is not the case, and are also more marked during 
fixation than when the gaze is inattentive. Nystagmus may increase or 
diminish during a certain direction of the gaze or in certain positions of the 
head; it is at times entirely suppressed by an unusual nearness of the object 
of fixation. In this case it is the convergence of the eyes that produces this 
effect; in fact, adducting prisms exercise the same action. 

The oscillations of the ocular globes are often accompanied by analo¬ 
gous movements of the head. These latter, as well as the movements of 
the eyes, are made round axes which are parallel to each other, but the rota¬ 
tions of the head are in the opposite direction to those of the eyes. (Alf. 

Apart from this anomaly, the rotations of the eyes may be executed 
with regularity in all directions, and the binocular movements are notably 
free from disturbance when no strabismus exists. However, the field of 
fixation, whether monocular or binocular, is notably reduced, especially in 

certain directions. 

From the point of view of etiology, and also of symptomatology, a dis¬ 
tinction must be made between congenital and acquired nystagmus. 

The former develops either very soon after birth or in early infancy. 
It is almost always associated with a weakness of visual acuity . 

The frequent relation between albinism and nystagmus has long been 
known, and it is to be readily explained by the imperfection of vision in 
eyes devoid of chorioidal pigment. Nystagmus may, however, be coinci¬ 
dent in certain cases with good visual acuity. It theny^afH^ests itself only 
when the vision is inattentive, and disappears duripgyfation. With cer¬ 
tain subjects an hereditary influence has been daQ^Sined. (Alf. Graefe, 
Lloyd Owen.) 

Persons affected with congenital nysta^J^when they are in a condi¬ 
tion to give satisfactory accounts of tl^i^^ion, do not complain of any 
trouble of the latter which is speci^U^Nmputable to the infirmity in ques¬ 
tion. It is noteworthy that they |(^ive no apparent motion of objects, 
and are annoyed only by the weakness of their visual acuity. In excep¬ 
tional cases, where the acuitjrts good, binocular vision exists, the limits 
of the field of fixation ^^otlnal, and the associated excursions of the 
eyes, as well as the am»«V&e of convergence, leave nothing to be desired. 

It is quite othe^wiyr in acquired nystagmus, which we ought to sub¬ 
divide into two categories, essential , idiopathic nystagmus, and the nystag¬ 
mus which is of lesions of the central nervous system. 

The foijH^i^—essential nystagmus—is, so to speak, a malady of occu¬ 
pation j^^ffects especially miners, and of them principally those who work 
in coa^^Knes. Attention having been called to it as long ago as 1861 by 
Hgta^ade, miners* nystagmus has been studied especially by Schroeter, 
. M^ren, Nieden, Snell, Dransart, and Romiee. 

Since nystagmus is much too frequent in the large population engaged 
> in the mining industry, we have asked our eminent colleague and friend 


Simeon Snell, F.R.C.S., of Sheffield, to communicate to us the results of 
the investigations which he has made on this subject in the mines of Great 
Britain. The following, somewhat abridged for this article, is the inter¬ 
esting reply which he has kindly furnished: 

“ Nystagmus, as occurring in miners, is characterized by the apparent 
movement of objects, either in a circle or ellipse; headache is often present, 
and especially giddiness, which sometimes causes the miner so to stumble 
about that he is compelled to leave his work in the mine. The movements 
of the globe are chiefly rotatory, and, though to-and-fro oscillations are 
sometimes superadded and are very rarely vertical, the first named are sel¬ 
dom if ever absent. The rapidity of the ocular motions varies greatly : from 
sixty to one hundred and fifty motions maybe counted in a minute; I have 
observed them as frequent as three hundred and fifty. Both eyes are af¬ 
fected ; the rapidity of movements may vary in the two eyes. The more 
rapid the oscillations, the less extended is the excursion of the globes.- The 
oscillations are arrested by turning the gaze downward below the horizontal 
line. Miners often rest their eyes in this way. Looking upward (levator 
muscles of the globe), and especially obliquely to one side or to the other, 
rapid movements of the head, lowering of the head and suddenly raising it, 
are means of increasing the rate of movements of the eyeball, or, in other 
cases, of rendering them evident. Placing the patient in the position he 
would assume at his work is another method. Associated frequently are 
tremors of the head (noticeable to the hand placed on the head), of the 
eyelids, and of the muscles of the face and neck; torticol^fe is met with ; 
night-blindness has been alleged to be present. Nied&^Spd Romiee and 
myself dispute its presence: the nystagmus alone kG^ufficient cause for 
any difficulty in seeing in a failing light. Errors or refraction, myopia, 
hypermetropia, and astigmatism are often pre^^but bear no causal rela¬ 
tion to nystagmus; visual acuity is genera]BjQ)naffected. Color-perception 
is good, and, so far as the oscillations pe^mj) uf testing, the field of vision 
is normal. The onset of the disorder i^often brought about by some attack 
of illness. It is generally met with la/men who have worked in the mine 
for some years. Ninety per cent^f cases occur in persons from twenty- 
five to forty-five years of age^V^ 

“ Nystagmus is found winners (coal-getters) engaged at the coal-face 
and who work in a nya?e(2piess constrained position of body and of eyes. 
It is desirable to get OQaJJ in as large pieces as possible, and to do this they 
undercut, or 6 holeQke seam. 1 A man sits with his legs crooked up lying 
almost on his sffifc^nd strikes the coal with a horizontal swing of his pick 
at the.botomQfc the coal-seam. He will cleave away the coal to a height 
of from^&hften inches to two feet, and then as he gets deeper in he draws 
his bodv uhder the coal, lying on one side or the other. The distance he 
maG^^iqercut the coal varies considerably. The process is called ‘ holing/ 

1 Miners’ Nystagmus, by Simeon Snell, F.R.C.S., Wright, Bristol. 



and sometimes the undermining may be continued from two or three feet to 
as much as seven or eight'feet. The miner applies timber supports to keep 
the coal from falling as lie proceeds with his work. As just described, it 
is called ‘bottom holing/ but; the seam may be attacked in the middle 
(middle holing) or at the top (top holing). A miner engaged at this work 
will direct his gaze to different parts as it becomes necessary for him to 
strike, for the eyes will follow the pick point, but the tendency will be for 
the be directed upwards (using the ocular elevators) more or less 
obliquely. He will lie sometimes on one side and sometimes on the other; 
his legs will be crooked up, his head thrown back and flexed more or less 
on the shoulder beneath. This position is shown in the photographs (Figs. 
57 and 58), which were taken in the mine with a magnesium flash light, 
of a man whilst actually at work. Ninety-eight per cent, of all cases of 
nystagmus coming under my observation have been occupied at the coal¬ 
face and more or less engaged in this kind of work. The thickness of the 
coal-seam varies greatly in different parts, but work of a very similar 
kind is done in coal-mines in all countries. 

“ Besides the coal-getters, there are others in a mine who attend to the 
roads, fill the wagons, push these ‘trammers/ or drive the ponies. There 
are also ‘ deputies’ or ‘ overlookers/ whose work it is to see to the safety of 
the places the men work in, both as to freedom from gas and as to the con¬ 
dition of the roof of the mine. These latter occasionally suffer from nys¬ 
tagmus, and if the work be analyzed it will be found to necessitate the same 
oblique, upward direction of the gaze, and generally these mqn have previ¬ 
ously worked as coal-getters. The photograph (Fig. 59<^Qrtys a ‘deputy’ 
examining the roof to ascertain its soundness by strikirf&rt with his stick. 
It must be remembered that the height of the work>^places and passages 
in the mine is nearly always so low that this al^arompels a constrained 
attitude. ‘ Onsetters/ whose duty it is to see Jpybh e ascent of the full and • 
descent of the empty coal-tubs, sometimes^eVriystagmus, as do also ‘tim¬ 
ber men.’ It may be accepted as a rule^hafall cases of nystagmus occur 
in those who are either working as dQj -getters or who have done so, or 
that the work in which they have b^^ employed has been one necessitating 
an upward look of the eyes fouj^^e or less prolonged periods. 

“What has been said wittJ^nt out the direction in which the etiology 
of the affection must be^s^uVht. Nystagmus depends on a chronic weari¬ 
ness induced in the lev^toj) muscles of the eyes by the constrained position. 
Like effects are fopqj^Jn other muscles of the miner, producing torticollis, 
tremors of the hp3y and quivering of the eyelids. It is thus similar to 
other occupati^yreuroses, and in the same category as those met with in 
writers, c :ors, telegraphers, ballet-dancers, and many others. 

“Nystagmus, besides possessing the peculiarities already mentioned, 
occu^j*wreJi all kinds of lighting. I have met with it in workers with safety- 
laftms^candles, large open lamps, and when the artificial light was good. 
iQy-^he other hand, there is some reason for believing that the strain is 


greater the worse the light, and that nystagmus is met with in greater fre¬ 
quency under such conditions. Other things, as nature of work, being 
equal, the disease will be most frequent with the bad light. Nieden and 
Dransart hold similar views. Romiee believes it to depend upon the efforts 
of accommodation induced by insufficient light, but it must be pointed out 
that the distance the miner is from his work is such that the accommodative 
effort can be but little if any. 

“ Nieden says that five per cent, of miners suffer. My observations sup¬ 
port this generally; though in some parts the percentage is higher (I found 
among men working with candles that six out of a total of one hundred 
and forty were absent from work for nystagmus, and this represented only 
a portion of those who would have been found to be actually affected on an 
examination of the whole number). Romiee gives twenty per cent, for 
Belgium; possibly he includes less marked cases. 

“ The prognosis is good, and, even in old standing cases, if the directions 
as to work are followed the nystagmus will disappear. Treatment con¬ 
sists in a change of work. In some cases it will suffice if the patient ceases 
from coal-getting, without altogether stopping work in the mine, but gener¬ 
ally it is advisable, especially if the nystagmus be of high degree and of 
some standing, to recommend cessation altogether of work under ground. 
Return to the mine is practicable after relief has been effected, provided the 
head can be kept straight and the upward turn of the eyes is avoided. 
Resumption of the old kind of employment is followed, sooner or later, by 
a recurrence of the symptoms. The patient’s health will ofte^Ve benefited 
by tonics, such as iron, and especially strychnia; in other ca^g*th% bromides 
are of service. Electricity has been used by some. AkjCJlie and eserine, 
suggested by Romiee for their effect upon the accoi^rHodation, are of no 
use, nor is the condition they are supposed to betel^present. Tenotomy, 
formerly advocated, is useless. 

“ The affection has been observed by me,{jr®ixhight under my notice by 
others, as occurring in compositors, a wjgfcer, plank-cutter (Nieden), saw- 
maker, iron-founder, fitter, roller, plate-fc^r (railway), and a youth carry¬ 
ing a tray on his head.” Jb 

Symptomatic nystagmus is in certain vices of conformation 

of the head and of the bra h^JS^ehlmann), in insular sclerosis (Charcot), 
especially when the sclera ks affect the fourth ventricle and the optic 
thalami (Raehlmann), inVjgjhorrhagic, embolic, or other lesions of the optic 
thalami , the fourth ve&jcle, the restiform bodies , and the cerebellum (Raehl- 
marin, Hitzig), in /E^toal infantile encephalitis, with secondary contraction 
of the eatfremi^^^Zehender). It may be consecutive to a traumatism 
(Nagel, Contracture by a fire-arm of the right temporal bone). At times 
it accompanied during the period of activity Cheyne-Stokes respiration 
(Merl^d^Y^inally, Friedreich has pointed out as among the symptoms of 
her^tary tabes a peculiar form of nystagmus which he designates by the 
n £mM>f ataxic . The movements of the eyes seem then incoordinate, like 


those of the lower extremities in the same malady. This interesting pecu¬ 
liarity has been found in several other cases of hereditary tabes described 
by other authors. 

These few anatomo-pathological data can scarcely serve to elucidate the 
etiology and pathogeny of congenital and occupational nystagmus. With¬ 
out doubt there must be made in this respect, as we have already said, a 
difference between these two forms. It has been sought to attribute con¬ 
genital nystagmus to a change in contractility having a peculiar bearing 
on one of the ocular muscles. Boehm was of opinion that the internal 
rectus was at fault. This author distinguished between tonic and atonic 
nystagmus, or sometimes an excess of power, sometimes a weakness, of the 
internal rectus prejudiced the normal equilibrium of the muscles of the 


It is probable that the diminution in visual acuity which so often ac¬ 
companies congenital nystagmus is in intimate relation to this anomaly of 
vision. But one could not affirm whether both are the parallel effects of 
some central lesion (Raehlmann) or whether the imperfection of sight is 
really the cause of the nystagmus. Yon Arlt, who holds this latter theory, 
believes that the oscillatory rhythmic movements are destined to increase 
the intensity of the insufficient visual impression made upon the retina by 
exterior objects. He bases this belief upon the fact that the object whose 
vision is rendered confused by a defect in optical adaptation, for instance, 
becomes more easily perceptible when it is shaken in front of the eyes. He 
also believes that the victims of nystagmus do not fix wit^the fovea cen¬ 

tralis, as do persons whose eyes are normal, which maiiH^psJthe constancy 
of fixation, but with some eccentric point in the vi of the posterior 

pole, so that the immobility of the gaze is indiffei^V But this theory in 
no wise explains the compensatory movement^Qhe head or the peculiar 
rhythm of the oscillatory movements, andjQs contradicted by the occa¬ 
sional high degrees of visual acuitv c^n^anble with nystagmus (Alf. 
Graefe). We have already discussed^&e role which heredity may play in 
the development of this anomaly. 

As to occupational nystagmn^&ttempts have been made to attribute it 
to peculiar toxic influences, 1 have been supposed to produce hemer¬ 
alopia. But, apart from or less pronounced ansemia, no other phe¬ 

nomenon of chronic npis^jipig has been discovered among coal-miners, and, 
according to von Rei^g^hemeralopia is lacking in many cases. Neverthe¬ 
less, the same awt©>j has found nystagmus in the case of an inspector who 
did not take pq ate the occupation of the workmen in the pits, which fact 
would se^n^^Sargue in favor of an action produced by coal-gas upon the 
central s system. 



intoxication might be due to the various gases which are generated in the mines. 
rrt)t know any exact fact relative to the influence of these gases upon the oculo- 
itor centres. As to other agencies being capable of an action of this sort, esei'ine must 
cited, since it, in the case of Zeliender’s patient, provoked nystagmus. 


However, the facts contributed by Magelson and Wilbrand, who have 
published cases of occupational nystagmus, which were altogether like that 
of miners, in seamstresses who are obliged to work with a poor light; and, 
on the other hand, the many cases in which nystagmus is associated with 
weakness or exaggerated working of certain muscles, the abnormal posi¬ 
tion which miners’ eyes must have during work (asymmetric convergence 
with elevation of the gaze),—all these facts incline to the supposition that 
fatigue of the muscles and exhaustion of their innervation must exert a 
great influence favorable to the development of nystagmus. This is the 
opinion advanced by Baer, and upheld by Alf. Graefe, Wilbrand, Dransart, 
and Snell. 

Every one is acquainted, indeed, with the chronic contractions presented 
by a muscle subjected to an exaggerated effort taking the place of the tonic 
contraction which is produced under the influence of the will when the 
muscle is not yet fatigued. It is highly probable that a similar phenome¬ 
non occurs in the ocular muscles in occupational nystagmus. 

Prognosis. —Congenital nystagmus presents only rare cases of sponta¬ 
neous cure. 1 As to occupational nystagmus, it is ordinarily curable in a 
shorter or longer time after the cessation of the existence of the cause by 
itself or under the influence of treatment. 

The prognosis of nystagmus caused by central lesion is subordinate to 
that of the lesions themselves. 

Treatment .—When congenital nystagmus is associated with a marked 
strabismus or with a refractive error, one may try to attenuate or suppress 
it by surgical and optical means. But congenital nystagmuAalmost always 
defies all kinds of treatment that may be directed againl^. 

As to occupational strabismus, we have nothing add to what Dr. 
Simeon Snell has said above concerning its treatme(m 

L One such case has been observed and reporb 


Graefe, loc. cit. p. 239. 


BY J. P. NUEL, M.D., 

Professor of Ophthalmology in the University of Liege, Belgium. 



Medical Director and Senior Ophthalmic Surgeon to the Union Mission Hospital, Phila¬ 
delphia, Pennsylvania, U. S. A. 


Diseases of the cornea constitute one of the most important chapters 
of ophthalmology, this being due to their serious consequences in regard 
to sight and their frequency. 

So far as their own importance is concerned, they all disturb the trans¬ 
parency of the corneal tissue, so that if they invade the central or the 
pupillary zone they lessen the clearness of vision. Indeed, they but too 
frequently destroy all useful visual power. In this resp^\conjunctival 
ailments are less disastrous; they attack vision only in aj^gendary way, as 
it were, through their complication with corneal disea^sG> 

As to the frequency and the importance of corntfj^lisease, our statistics 
based upon the records of twenty thousand ca^k^f affections of the eye 
show that from one-fourth to one-third of a«U*(qyRhalmic disturbances con¬ 
sist in such diseases. Such is the proporflvfti/ generally found. In coun¬ 
tries where granular conjunctivitis is^p^emic, the relative frequency is 
somewhat less. 

From observations made byifekhoff on ten thousand blind people, it 
appears that in over thirteen pg^cept. of cases blindness is the consequence 
of corneal affections. If t(^^^Se are added the cases in which blindness is 
consequent upon blenn ofrilQt ^(a result that is likewise produced by corneal 
complications)^ it will Bfcbiound that in more than twenty-seven per cent, 
of cases—that is toG^y, in more than one case out of four—blindness is 
due to corneal afl^cybns (see vol. ii. p. 432 et seq.). 

With r^ftpChe to the frequency of corneal disturbances it is well to 
recall the v that, first of all, this membrane is, of all portions of the 
eyeball^flhe most exposed to external injuries; and that, secondly, it is not 
with blood-vessels. In addition, its different parts (especially 

’al zone) are quite a distance from the nutrient vessels, and hence, 




to a certain degree, notably as compared with the conjunctiva, it lacks 
sufficient strength to' combat the causes of disease. Nevertheless, clinical 
experience teaches that in the case of pathogenic influences that are not 
microbic, such as traumatic disturbances, for instance, the cornea can very 
well take care of itself. Its regenerative processes are almost as rapid as 
those of the conjunctiva, and are much more energetic than those of the 
fibrous tissues, such as the sclerotic. 

As soon, however, as the reparative processes are complicated by mi¬ 
crobes, the cornea displays a notable inferiority of regeneration in compari¬ 
son with the conjunctiva. It seems that the cornea’s relatively abundant 
stock of nutritive fluids and interstitial lymph is generally sufficient, as in 


the conjunctiva, for regeneration, when they are unimpeded by septic poison¬ 
ing, to take place. If, however, there is pathogenic microbic complica¬ 
tion, regeneration is delayed, and in too many instances the microbes gain 
the victory, this being much more frequently so than with similar changes 
in the conjunctiva. The reason of this is that the struggle against microbic 
influences is, above all, a function of the migratory cells (phagocytosis). 
In the cornea these cells frequently have a very long distance to extend 
before they reach the spot that is attacked by the enemy. In the cornea it 
is especially in the centre of the membrane that microbic infection develops 
and spreads the most easily. 

All portions of the structure of the cornea are subject to the influence 
of ordinary pathogenic causes,—physical, chemical, and microbic,—but they 
are not equally susceptible to alteration of nutrition h\ consequence of 
such noxious influences. Bowman’s membrane and ijkOij^line lamina of 
the membrane of Descemet are relatively slow t(g£fke on pathological 
processes. On the other hand, the epithelial ^ySthe endothelial layers 
react as energetically to pathogenetic causey^ploes the substance of the 
cornea proper. Alterations, however, that^sSjyTimited to these membranes 
rarely produce changes that are suffici^^^veep to injure vision seriously, 
and hence, unlike those of the sulfeantfa propria, can hardly merit the 
name of maladies in the clinical of the word. From this point of 

view, however, it seems that th^^le of the epithelium has in the past been 
too much neglected. 


Under the evarious influences (traumatic, poisonous, etc.), the 
tissues of the cornea react against certain processes, which, when a sufficient 
intensity of reason is attained, are designated by the generic term of “ kera¬ 
titis,” qf y^iflammation of the cornea,” this expression being borrowed 
from theories. The manifest purpose of such inflammatory reac- 

iX^lie repair of injury. The wounded elements are devitalized, are 
ed or are detached, and the resulting gaps are filled in, brought to- 
v gs^ier, repaired, and cicatrized. When, in consequence of a superficial lesion 
^Qbf the corneal epithelium encroaching even but slightly on the substance 



proper of the cornea, the neighboring epithelial cells alter their form, become 
active, and proliferate to fill the gap, this condition, however, is not, generally 
speaking, characterized as an inflammation. The line, nevertheless, at which 
the inflammation or keratitis in a clinical sense begins is not clearly trace¬ 
able. In the example cited, there is certainly a keratitis, but the condition 
is of too little importance to be considered as such practically. The loss of 
substance once being regained, keratitis is no longer spoken of, although 
the cicatricial tissue may continue to change and to attempt to reapproach 
a normal state. Again, there is no distinctly traceable limit between corneal 
inflammation and the cicatrized tissue. 

From a histological point of view, the various forms of keratitis can be 
especially noted by tracing them from the least to the most complex varie¬ 
ties. A simple case is that of an incised wound of the cornea which 
cicatrizes without the intervention of pathogenic microbes. The slight 

Fig. 1. 

Vertical incision of the cornea: commencement of cicatriz^imjrthe end of the second day; 
gaping of the wound; disposition of the epithelium lining thelffl^BTes into two layers, as similar as 
possible to the normal epithelium of the cornea. Some cells can be seen in both lips of 

the wound, especially towards its bottom. 

wound gapes on account of a retractof the divided corneal lamellae. 
In two hours’ time the neighboring^Ditnelial cells are set into motion and 
wander along the borders of the At the end of from twelve to twenty- 
four hours’ time they cover hotf^orders of the incision, including even the 
bottom of the gap. (Fig. A) There is a multiplication of the epithelial 
cells by subdivision (karyyWnesis), these being found partly in the wound 
and partly at a distance n*om the surface. Close by the incision the divided 
corneal lamellae swollen, the interfibrillary spaces distend (oedema), 

and after some a few migratory cells appear. At times, the epithelial 

plug occunA^bre or less of the gap, starting to fill it in from the bottom. 
Always, hoover, the epithelial cells have a tendency to group themselves 
into ddi^Aayers, one for each side of the wound. Finally, in consequence 
of^heVpproach of the sides of the wound to one another, the epithelial plug 
isJiG/fced to the surface. The corpuscles of the cornea proliferate around the 



incision, and the cicatrix of the tissue proper becomes marked by a moderate 
accumulation of young cells; these being transformed into fibrillary tissue, 
which for a long time, because of its irregularity, is discoverable under the 
microscope. The oedema disappears, and the epithelium, in the normal course 
of the healing process, follows in advance of the cicatrix. [If the incision is 
deeper the processes are more complex.] A common condition is that in which 
the incision has traversed the entire thickness of the cornea. If, under such 
circumstances, the wound does not gape too much, its two lips will come in 
contact by the median corneal planes. As a rule, the retraction is greatest 
before and behind, and at these points the tissues do not come in contact. 
The anterior interspace becomes filled in by the process above described. 
The posterior opening towards the anterior chamber is at first filled by a 
plug of fibrin which is furnished by the ciliary body and the iris. This 
plug is later infiltrated by migratory cells and transformed into cellular 
tissue, which is reconstituted into fibrillary material. The endothelium 

Fig. 2. 

Provisional occlusion of a corneal perforation (of a rabb^pNpft plug of fibrin. To the right and 
the left are the two cedematous lips of the corneal worn are three successive layers of fibrin 
which have been successively formed. The wound is ot \wq/ hiys’ duration. Some few migratory cells 
appear on the lips of the wound, and in the two lat^r formed layers (/',/') of fibrin. The epithelium 
has emigrated in front of the plug of fibrin, whioif^Njovers only as far as E E. 

slides over the plug, and later, kMaf process analogous to that which is oc¬ 
curring in the epithelium, iti^kp-s into a continuous layer. The emigra¬ 
tion of the endothelium\mys a less important role in the process of 
cicatrization. BehindfthQnterspace is filled by the insertion of fresh cellu¬ 
lar tissue which is miV^/more abundant than that which closes the wound 
in front. The sm^Sijprane of Descemet does not always completely reform. 
The epitheliun^^mes down little by little along the sides of the inci¬ 
sion in a ^jHmHaous layer of one or two cells, and in twenty-four hours’ 
time a reached at which the adjoining sides of the wound touch, the 

layers tof the two sides meeting one another. Emigration continuing, the 
ceij£ , Ho^imulate at the bottom of the incision, filling it more or less, though 
ii^reiy entirely. Henceforward, the tendency is to leave the central space 
o5ft*ee. The superficial cells become flattened, and the deeper ones assume a 




cylindrical form which is perpendicular to the sides of the incision (as in 
the normal epithelium). 

The epithelial cells multiply on the surface of the cornea as well as in 
the excavation. The cedema of the cornea extends more or less distantly. 
From the second day there is a rising in the tissue proper towards the 
edges of the wound, the migratory cells coming from the pericorneal ves¬ 
sels. There is, moreover, karyokinesis of the fixed corneal cells. The 
young cells of both productions penetrate beneath the immigrant epithe¬ 
lium, especially in the bottom. In this situation they constitute young 
cellular tissue which drives back the epithelium towards the surface, at the 
same time that the sides of the incision approach one other. 

If the lips of the wound do not come in contact at any point, the plug 
of fibrin plays a more important role . At first it establishes a temporary 
closure (Fig. 2), after which the process of cicatrization becomes analogous 
to that which occurs in the preceding case. The iris may also be engaged 

Fig. 3. 

Provisional occlusion of a perforating woumj 
To the right and the left are the lips of 1 
wound, to the lips of which it is united 1 
the iris. The corneal epithelium has 1 
Some few migratory cells which haveJ 

|the cornea (of a rabbit) dating some eight hours, 
wound. J shows the iris engaged in the corneal 
is a thick plug of fibrin which has exuded from 
ligrate over the plug of fibrin, but only as far as EE. 
penetrating the plug of fibrin. 

in the wound (Fig. 3), ^jih it more or less fills. The iris is covered in 
front by a layer of % in, and the subsequent processes are virtually the 
same.—In the prQcling cases the migratory cells have been furnished by 
the cornea; {h^Ovave sprung from the pericorneal vessels. When, how¬ 
ever, there^^rattachment of the iris, its vessels become equally a source 
of migrating cells.—The iris establishes adhesions to the lips of the corneal 
wounliQjjs tissue rests fixed in the cicatrix, forming an anterior synechia, 
to the origin of this fibrin of the plug, it must be borne in mind 
e normal aqueous humor contains hardly any albuminoid substances. 


Re-formed after puncture of the corneal wall, albumin which is coagulable 
by heat and fibrinogenous substance are found in it. In the opinion of 
Greeff, the reason of this is that, after puncture, the epithelium of the 
ciliary processes rises up in vesicles. The tissues, thus stripped of their 
covering, allow the transudation of the plasma sanguinis which, in its 
normal condition, is held within the vascular channels by the epithelium; 
and it is this plasma that contains albumin and fibrinogen. Such, then, 
appears to be the origin of fibrin, consequent upon simple puncture of the 
cornea. In the frequent instances of corneal perforation through ulcerous 
keratitis associated with iritis and hypopyon, the iris assuredly supplies a 
portion of the fibrin that is contained in the anterior chamber. (See 
Hypopyon.) Besides, under these circumstances, the anterior surface of 
the iris is also affected; its endothelium is disturbed and even lost in spots. 
(In the case of Fig. 3, there is no doubt that the iris also is a source of 

(a) Cicatrization following Loss of Substance .—Frequently there is a loss 
of substance, of greater or less extent in depth, on the surface of the cornea, 

Fig. 4. 

Cicatrized ulcer of the cornea: / r< 
it in the form of plugs; g , g design: 
the membrane of Bowman; e sigT^fil 

the epithelium covering the cicatrix and penetrating 
orders of the cicatrized ulcer, showing interruption of 
icial tissue. (Saemisch.) 

caused by a traum^!Tsrn<as, for example, a cauterization. At other times 
the loss of substan^^ccurs in consequence of an ulcer, in which case the 
bottom of the c^JJy is strongly infiltrated with migratory cells.—The cavity 
can no Ion; obliterated by the approach of the lips of the wound to 

one aiWh&v it will become filled by cicatricial tissue. The repair com- 
mence!\h^ an emigration of the epithelium that lines the bottom of the 
ca-wjA, followed by an accumulation of the young cells beneath it, which 
it. In consequence of this the cicatricial tissue, which is at first 
cellular in character, becomes fibrillary in type and the cicatrix remains 
er more or less opaque. (Fig. 4.) 



Under the microscope the fibres are distinguishable from normal corneal 
tissue by a certain irregularity. Bowman’s membrane is not reconstituted, 
the epithelial layer being irregularly limited towards the deepest part. 

(6) Corneal Infiltration .—When, by means of a Pravaz syringe, a cul¬ 
ture of staphylococcus is injected under the lamellae of the cornea, the 
tissue involved becomes necrosed to a certain extent; migratory cells are 
brought in great number by the pericorneal vessels and collect at the edge 
of the necrosed tissues. One of their roles is to act as a barrier to the 
wide-spread invasion of the microbes (phagocytosis). The corneal lamellae 
become cedematous for some distance; they are softened; and at last are 
dissolved at the edge of the necrosed parts. It is assumed that the migra¬ 
tory cells finally conquer the microbes. The latter are digested and ab¬ 
sorbed with the necrosed portions if they are not in too great numbers. It 
sometimes happens that the corneal layers lying above the injection are in¬ 
cluded in the necrosis; the whole is then detached and expelled, and the 
injured part becomes transformed into an open ulcer. In the end, repair is 
carried on by a similar process to that above described, with this difference, 
that the vicinity of the lesion is infiltrated by young migratory cells to a 
greater extent than it is in the repair of an aseptic lesion. 

The term infiltration is given to the condition in which there is such an 
appearance in the normal elements of the cornea of those heterogeneous 
elements that more or less alter the transparency of the membrane. This 
infiltration material may be composed of a liquid (causing oedema), of pre¬ 
cipitated substances, albuminoid matter (fibrin, etc.) in the form of gran¬ 
ules, of microscopic filaments, and, finally, of cells. 

Most frequently cells predominate m the mfiltratic^^nass. They are, 
however, always accompanied by oedema and by^^tanular precipitate. 
An example of cellular infiltration is that wl produced around an 

injection of staphylococci in the cornea to ma^mmi it. One is disposed to 
admit nowadays, without sufficient reasoiTmat all well-marked cellular 
infiltrations are the result of “ microbic^fection” through the penetration 
of pathogenic microbes into the tissue ^bper of the cornea. 

It is to a great extent depern upon the results of experiments on 
the cornea that Metschnikoff foujtt&d his famous theory concerning jihago- 
cytosis. Since then, it has^^r generally admitted that the wellnigh ex¬ 
clusive purpose of cellufciQmltration is to combat microbes. It is also 
admitted that phagocytosis and, consequently, cellular infiltration are the 
principal means of iS^-defence that the cornea puts forth against microbic 
invasion,—the ba^pcidal power of tears being too trifling to be taken seri¬ 
ously into any more than that of the aqueous humor in the case 

of corneal>^i^oration. 

It i^Vinquestionably true that the penetration of pathogenic microbes 
into tissues produces an immigration of young cells. It is likewise 
cerainthat, in the great majority of cases, cellular infiltration of the con 


{paused by the presence of these microbes. It does not, however, appear 



certain that the process of combating microbes is the sole function of mi¬ 
gratory cells. These cells seem to furnish a dialytic substance which softens 
dead tissues around the edges of healthy parts, and thus helps the unloosing 
of the dead portions (Leber). Finally, migratory cells contribute directly 
to the digestion, to the absorption, and to the removal of granular and 
other materials that have become unfit for the nutrition of the tissues 
(macrophagi). If, then, in the depth of the cornea there is deposited a 
substance—whether of an irritating nature or not—that is safe from mi- 
crobic infection; if in consequence of disturbances in the general nutrition, 
nutritive anomalies, as yet ill-defined, manifest themselves in the cornea, in 
each and all of these conditions, migratory cells will speedily make their 
way (although in less quantity than in microbic infection) towards the 
affected spot, like so many ants hastening to their prey, in order to con¬ 
tribute to the absorption of the anomalous deposits and of the affected cor¬ 
neal elements. 

The corneal infiltration may be superficial, involving only the epithe¬ 
lium, or is deep from the first onset. (Fig. 5.) Cellular infiltration is always 

Fig. 5. 

accompanied by «^a, the infiltrated portion being more or less clouded, 
according to its^msity. The epithelium is always exfoliated at its level, 
this being ^nd^pronounced as the infiltration is the more superficial. This 
exfoliatifl^^unically, is indicated by a dulness of the corneal surface. 

Thdlre are diffuse forms of infiltration (see Parenchymatous Keratitis ), 
(^lyejr varieties that are more circumscribed. A circumscribed form of 
fterrfcial infiltration may produce a bosselated appearance of the corneal 
face. (Fig. 5.) 




Infiltrated corneal ulcer. (After Alt.) (Edematous corneal 
lamellae curved towards the surface of the ulcer. The epithelium 
is about to descend into the ulcerous area. 

If the infiltration is not too dense, it may be absorbed without leaving 
an appreciable trace; otherwise a cicatrix, which appears as a permanent 
macula, remains. When 

the infiltration is more Fig - 

notable in extent and in 
intensity, the infiltrated 
corneal tissue softens or 
becomes necrosed. In such 
a case it is preferably 
known as suppurative 
keratitis . This form al¬ 
ways appears to be due to 
a microbic infection, and 
the infiltration, extending, 
reaches the epithelium. 

Bowman’s membrane is 
uniformly softened, the epithelium is raised, and the infiltration area 
changes to an ulcer, the fundus of which is completely occupied by cells. 
(Fig. 6.) 

(c) Corneal Ulcer .—Such an ulcer is always infected,—that is to say, 
pathogenic microbes play an important role in its evolution. 

It happens in a well-formed ulcer that the infiltration ceases to extend, 
and repair begins. At other times, when the microbic infection is pro¬ 
nounced, the ulcer invades healthy corneal tissue and becomes deeper and 
broader (progressive ulcer). Sooner or later, however, thertl^ntial attri¬ 
butes or properties of the tissues (phagocytosis, etc.) oraNuer the patho¬ 
genic microbes, opposing to them an insurmountabl^ferrier of cells,—a 
zone of infiltration. This process produces an arr£SOs>t the ulcer in which 
the mass becomes regressive, and cicatrization mwSeds as described above. 

In every case of well-marked keratiti^l&p^ially in the suppurative 
form, the area of focus affected is surroun^ecHby a collateral oedema. There 
is congestion of the nutrient vessels of(0e cornea, and often of the vessels 
of the iris. /> 

(d) Microbic Infection . Exofemfis and Endogenous Mici'obic Infec¬ 
tion. —According to the cheAwJf meory of inflammation in general, and 
especially of microbic inflarfrarafcion, the intra-corneal pathogenic microbes 
produce phlogogenic sub^aj/ces, toxines , the chemical nature of which is but 
little known; these^apecmfused in every direction, particularly towards the 
periphery of the co**S^and in the anterior chamber. In the first direction 
they reach th£ Jfl^icorneal vessels, which they paralyze and whose walls 
they alter, aHd^feftus provoke exudation of plasma and emigration of leu¬ 
cocytes, whick are attracted by these substances towards the region of infec¬ 
tion, ^nd^Dnstitute corneal infiltration. In the direction of the anterior 
chaf^bel^if the toxines are sufficiently numerous, they reach the iris, where 
tWWause the same vascular alteration, exudation of plasma, and emigra- 
ly vol. iy.—12 



tion of cells,— i.e ., iritis. The exudation, especially the cells, may accumu¬ 
late on the bottom of the anterior chamber under the name of hypopyon . 
These substances alone, isolated from the microbes and inoculated in the 
cornea (Th. Leber), are sufficient to provoke all the symptoms of microbic 
inflammation. 1 

As said above, it is supposed also that in all changes in the normal 
nutrition of the human tissues,—for example, in consequence of wounds or 
as the result of deposits of some heterogeneous principle,—there are pro¬ 
duced phlogogenous substances which are analogous to, if not identical 
with, those of pathogenic microbes. 

Microbic infection, the principal cause of cellular infiltration of the 
cornea, is nearly always exogenous in type. The microbes penetrate the 
corneal tissue proper through lesions that are sometimes purely epithelial 
in character. When the epithelium is intact, it presents an almost insur¬ 
mountable barrier to them. It may be said that in all cases of ulcerous 
keratitis, whether it be superficial or deeply seated, if there is microbic 
infection—and that is always the case, either primarily or secondarily—it 
is exogenous in type. 

Most frequently the infecting microbes in the exogenous form of infec¬ 
tion are the staphylococcus aureus and the staphylococcus albus; often the 
diplococcus of Frankel or pneumococcus (Gasparini, Uhthoff, and Axen- 
feld); and, less often, the more virulent streptococcus. Imperfectly de¬ 
scribed bacilli have been found in a few cases of this kind. 

Endogenous microbic infection is very exceptional. iSome microbes, 
coming from the pericorneal blood-vessels, after pen$tffcti*g the subcon¬ 
junctival tissue, might perchance pass into the co6^a by means of the 
interstitial lymph-spaces. This form of infection^^ms to be established in 
the case of tuberculous parenchymatous keratins) and perhaps also in that 
of leprosy. But the last case is a variety off&pfgenous infection, the bacilli 
of leprosy penetrating the pericorneal tfcsite Erectly, instead of being con¬ 
veyed by the blood-current. St 

In the more frequent cases of^pliilitic parenchymatous keratitis, it 
is not known whether the poi^0jus substance which penetrates the deep 
lamellae of the cornea—alw^vlj^ought into position by the blood-currents 
—is a microbe or a ch^rfell substance. According to all appearance, 
noxious chemical suhsh®el that have been conveyed by the blood-currents 
or formed in the pdjjc^neal tissue and have penetrated the cornea are the 
cause of certain of deeply-seated, non-ulcerous keratitis (in gout, for 


A secen^f^nn of endogenous infection would be that in which microbes, 
lin ^the depths of the eye by means of the aqueous humor, would 


give an idea of the attraction that is exercised from afar by phlogogens over leuco- 
cpS^syit^rnay be recalled that the antherozoids of ferns are attracted by malic acid, those 
moss by sugar of milk, and mobile bacteria by peptone; and that the one-trillion th 
►>i mrt of a milligramme is sufficient to produce this effect. (Pfeffer.) 



penetrate the cornea through its posterior surface. The certainty of this 

method of corneal infection has not been established beyond question. On 

the contrary, what seems a rather frequent occurrence is that, in certain 
deeply seated atfections of the eye (cyclitis, for example, and perhaps also 
scleritis), substances that are more or less noxious, but are not microbic in 
character, pass into and irritate the deeper layers of the cornea, including 
the endothelium, and produce localized cellular infiltration. 

Formerly—and the practice still holds nowadays—simpi e-mon-infected 
ulcers were discriminated from infected and suppurative ulcers of the cornea. 
From a clinical point of view this point will be continued, but it must be 
borne in mind that in the former variety (the non-infected) there is infec¬ 
tion through pathogenic microbes, although the infection is very trifling 
either because the microbes are less virulent or less numerous, or because 
the bactericidal power of the cornea is greater. On the other hand, by the 
term “ infected ulcers” will be designated those cases in which a greater 
progressive infection is differentiated from a stronger local accumulation of 
young cells, and a more intense distant reaction (ciliary injection and iridian 
phenomena). Lastly, the term “ suppurative ulcers” will be used when the 
accumulation of cells in the ulcer is very great, and especially when there 
is pus in the anterior chamber. 

(e) Formation of Vessels in the Cornea; Pannus .—The regression of 
somewhat extensive corneal infiltrations and of ulcers of notable dimension 
is marked by the appearance in the corneal tissue proper of vessels which 
later disappear. In such cases this condition is a phenomenon of good 
omen; it strengthens % the nutrition of the cornea, assists^h\the resorp¬ 
tion of the exudations, and helps in the struggle aga«Sr the invading 
microbes. Nevertheless, there are certain forms of sm^frcial cellular infil¬ 
tration that are accompanied by a vascularization wW proceeds from the 
superficial pericorneal and even from the cwjtfnctival vessels. This 
variety exhibits a tendency neither to disaptf&fhS^pr to suppurate, but tends 
to become definitely organized. Such teisSrfarization, in some measure 
made an integral part of the pathologic$\process, is not a favorable symp¬ 
tom. The name of pannus is givewntothese forms of superficial cellular 
infiltration and vascularization. (&ejtT > hlyctenular Keratitis , and especially 
Granular Pannus .) At first ^fo@lsmilarization is situated under Bowman’s 
membrane, which it later wf^g^s and penetrates beneath the epithelium. 
In deep keratitis (paren^i^natosa) the vessels proceed from the deep peri¬ 
corneal vessels and argsituated in the deep lamellae of the cornea. 

(/) Corneal —Corneal inflammations, traumatic, microbic, etc., 

are always accgn^p^rfed by an oedema which extends more or less beyond the . 
poition that^^^tytared, infiltrated, or infected by microbes. The oedematous 
part is swoIIcti and thickened. Clinical examination shows a diffuse dis- 
turbanra*Jlmt is uniform and smoky in appearance. Sometimes it is more 
ms and even appears striated (dilatations of the inter- 

The corneal surface at its level is slightly dulled. 



Microscopically, the interlamellar spaces are seen to be distended and the 
lamellae are held apart by a clear liquid. Some migratory cells may ac¬ 
cumulate in the cedematous parts, but they disappear before the oedema 
passes away. The disturbance is not due to their presence. Liquid may 
infiltrate between the epithelial cells, distending the intercellular lacunae, 
while the epithelium may frequently irregularly exfoliate. In consequence, 
the cornea becomes turbid, or the liquid may elevate localized areas of the 
epithelium in the form of vesicles. The oedema surrounding a traumatic 
keratitis is partly a product of inflammation and partly an infiltration by 
tears and aqueous humor through the wound. The simple removal of the 
corneal epithelium or endothelium gives access to liquids (aqueous and 
tears) overflowing it, which impregnate and disturb the corneal tissue (Leber). 
Non-inflammatory oedema due exclusively to this cause will be met with. 
The corneal oedema of acute glaucoma appears to result from a stasis of the 
corneal lymph. The corneal oedema of superficial punctate keratitis, being 
wholly inflammatory, is unaccompanied by cellular infiltration; it is an 
inflammatory form of lymphatic stasis. 



To expose the cornea the fingers of one hand ordinarily suffice. The 
employment of cocaine is recommended as a general measure to facilitate 
exploration. Exceptionally (as in extreme swelling of the conjunctiva, 
violent blepharospasm, etc.) it becomes obligatory to use the hook-shaped 
retractor of Desmarres. Chloroform narcosis is never n^dessary. 

The treatment of an ocular malady in general shpmjj.*ever be com¬ 
menced without having the cornea, the conjunctiva, j0i 'anterior chamber, 
and the iris well examined. Not only should tli^^)k done on account of 
the responsibility involved, but also to have tL^^jme of the significance of 
the symptoms that have been determined mirf^fftoroughly understood. 

General Clinical Symptoms of KerafttS.—In order to have the con¬ 
dition known as keratitis, it is necessaf^tonave the following three pathog¬ 
nomonic symptoms: 1, corneal disturbance; 2, inequalities or dulness of 
the corneal surface; and 3, cilijnj0^ijection. 

1. Corneal Disturbance.jJ^Ly or yellow discoloration in varying de¬ 
grees may be present. SAutef epithelial lesions produce this discoloration 
only to an insignificgjijQicgree. If it is trifling, the naked eye cannot 
observe it, especially\ if j he iris is clear. When the eye is directed so that 
the spot is projqptgLin front of the black pupil, the disturbed area becomes 
more plainly yr^We. Oblique, focal, or lateral illumination (see Special 
. Article , vcfl^hvp. 27) will decide in difficult cases when other symptoms 
give ri^N^C^uspicion of keratitis. If the disturbance is very circum¬ 
scribed superficial, a presbyopic observer should provide himself with 
x lens of two to twenty diopters. If he wishes, he may use a 
ke*s loupe. The binocular loop of Zehender, etc., and the corneal 
microscope (see vol. ii. p. 27) have also been employed to advantage. 



The use of these is complicated, and should be reserved for researches that 
are special in character. 

The appearance of inflammatory disturbance may be profitably inten¬ 
sified or even made quite discernible by coloring matter that is made to 
penetrate the corneal tissues through epithelial lesions. A drop of a two 
per cent, strength aqueous solution of fluorescine gives a greenish-yellow 
color to the substance proper of the cornea, and resorcine, in two per cent, 
strength aqueous solutions causes it to assume a reddish-brown color. In 
this manner an exact idea of a corneal lesion—for example, a superficial 
abrasion—can be formed. Old corneal spots and maculae are not colored, 
nor are deep corneal oedemas or deep infiltrations, if the epithelium is intact. 
This is also the case when there is simple deposit on the posterior surface 
of the cornea. 

2. Dulness or Inequalities of the Corneal Surface .—A simple dulness in 
the plane of an inflammatory infiltration, and even before any corneal oedema 
reaches the surface, may only be seen directly by binocular vision. This is 
also true when there are slight excavations, ulcers, etc., of the corneal sur¬ 
face. This in a measure can be determined by observing a regularly formed 
image made by reflection on the corneal surface. To do this, the eye to be 
examined should be placed a little in profile before a window, when, if the 
corneal reflection is normal, a small plain image of the window may be 
recognized. If there is an irregularity of the surface, the straight lines of 
the reflected images are diffused, etc. In the case of ulcer or of marked 
elevation in the cornea, the image of the window is scarcely recognized, but 
the configuration of the cornea is determined. By mean^c^he moving 
finger the eye examined should be directed in such mam^jOte to bring suc¬ 
cessively the different corneal segments to any poinl^Qwhich the corneal 
reflection is found. A slight dulness may be qha^rbd by the tears, this 
condition reappearing if the eye be kept open fq^m brief period of time. 

3. Ciliary Injection .—The cornea is noiuisraeS exclusively by the peri¬ 
corneal vessels, both superficial and dee$t wmch are subdivisions of the 
anterior ciliary vessels. The superficial (g^es preside rather over the nutri¬ 
tion of the anterior corneal planes, th0prneal conjunctiva, and the limbus 
conjunctival is, while the deep on^Wmtrol the circulation of the deeper 
planes. In every fairly marl^JC&se of keratitis both sets of vessels are 
congested, but the superfki^jalone are visible—although the trunks are 
common to both. The lij^l of the ciliary veins is red, just as is that of 
the conjunctival veins^iis being caused by hsematosis from contact with 
air passing througl^^ conjunctiva. The nourishing superficial capillaries 
of the cornea ^jOfeund in the limbus conjunctival is. Capillary injection 
constitutes, gratingly, a roseate band that is situated around the cornea. 
It is generdJ, n the keratitis is central or very extensive, and it is localized 
or verMmi^ed at some particular point, if the keratitis is peripheral. Fre- 
quei]p£, the conjunctival vessels are dilated and conceal more or less the 
ciJO^injection (collateral hypersemia). In fact, there can be a conjunctival 



catarrh, which may be the cause or the consequence of a keratitis. It is 
important to distinguish between the two forms of injection, the inflamma¬ 
tion of the cornea being generally the more important and the one de¬ 
manding special treatment. (For conjunctival injection see Diseases of the 
Conjunctiva .) Some of the differential points are, (a) injection of the ciliary 
capillaries reaches its maximum near the cornea, and diminishes towards 
the equator of the eye, as opposed to conjunctival capillary injection ; ( b) 
the injection of the ciliary capillaries is frequently unequal or partial, while 
the conjunctival is general; (c) the large ciliary trunks lose themselves in 
the deeper parts of the sclera before they arrive at the cul-de-sacs; (d) 
the ciliary vessels run serpentinely without giving origin to any large col¬ 
lateral branches, while the conjunctival ones subdivide in an arborescent 
form ; (e) the conjunctival vessels distribute themselves only in the conjunc¬ 
tiva ; (/) the conjunctival vessels are of a cinnabar-red color, while the 
ciliary ones are violet in tint, (g) The former can be displaced laterally by 
incurving the conjunctiva; the latter are fixed and traverse the sclera in 
regular grooves. In chronic glaucoma, for example, the ciliary trunks 
alone are injected. The pericorneal capillaries are injected in diseases of the 
cornea, of the iris, and of the ciliary body. 

Symptoms of Relative Gravity of Keratitis.—It is essential to 
observe all the symptoms of keratitis. Among them, however, there are 
some which denote an exceptional gravity of the malady,—that is to say, 
the danger of harmful infection and complication with iritis is sufficient to 
render necessary a special form of treatment, such as at^cfoine, antiseptics, 
and occlusive bandages. A keratitis is always grave, ^^damands particu¬ 
lar care, first, when it is pronounced and involves dl^cfeep corneal layers, 
and, second, when it is strongly infected. In tjtf\mtter case the phlogo- 
genic substances are diffused in the deep coiw^yjnanes and much further 
(in the aqueous humor and in the irisVm^pking the symptoms of pro¬ 
found keratitis. Direct inspection of thi cyueal lesions is not always suffi¬ 
cient to decide if they involve the corneal planes or if the structures 
are infected. The intensity of an Qsitration is not an absolute criterion 
of the degree of the infection^ profound one may be concealed by a 
superficial disturbance. As^QjHe, however, it is difficult to determine the 
level of any form of sud^vjpitration. The corneal lamellae of the bottom 
of a deep ulcer may^ MSS® be swollen and project even to the surface, etc. 

As it is, therefoA^j^ldom possible to ascertain by direct in-pection the 
relative gravity^ A. depth or the degree of infection of a case of keratitis, 
it is of importa^Ne to .pay attention to the following symptoms, which al¬ 
ways revoal^iegravity of the disease. 

Th^S^^mptoms are: 1, congestion of the iris; 2, intolerance of irri¬ 
tating^ drags ; and, 3, the formation of deeply-seated vessels in the cornea. 

ymptoms of Congestion of the Iris .—The cases of profound keratitis, 
iof aseptic or septic infiltration, and of deep aseptic wounds, as well as 
Venose that are manifestly infected, are always accompanied by a group of iris 



symptoms, which most frequently are due to congestion of the iris tissues. 
In extreme cases the dilated vessels of the iris can be seen, but this is not 
generally so; so that it becomes necessary to judge of this by indirect 
means. These symptoms of congestion of the iris are the following: (ct) 
contraction of the pupil; (b) sluggish action of the iris; (c) discoloration 
of the iris; and ( d ) ciliary pain (see Diseases of the Iris). When posterior 
synechia is added there is iritis, which is characteristic of serious forms of 
keratitis. The greater part of these symptoms, with the exception of the 
discoloration of the iris and synechia, may give rise to a spasm of the 
sphincter muscle of the pupil. Spasmodic myosis is also accompanied by 
ciliary pain. The condition is also observed in cases of somewhat exten¬ 
sive superficial keratitis, being caused by irritation of the corneal nerves. 
If the affection is situated even moderately deep or if it is infected, it will 
be complicated by a true hyperaemia of the iris. In profound or in infected 
cases the myosis is at the first onset congestive in type. It is a collateral 
oedema that is capable of progressing to inflammation, this result probably 
being dependent upon a diffusion of phlogogenic substances from the cornea 
towards the iris. Dilatation of the vessels of the iris distends the mem¬ 
brane and also contracts the pupil. 

Ciliary pains result from a twitching of the nerves of the iris. They 
cease as soon as atropine dilatation of the pupil is reached, but if atropine 
fails to dilate the pupil, etc., they continue in consequence of synechia. 
They radiate over the forehead and even extend to the cheek, being very 
characteristic of a profound keratitis. It is necessary to distinguish them 
from so-called superficial pains, which consist of sensation&^Jf scalding, of 
heat, and of foreign.bodies located in the eye or in thej^glkr; these being 
mainly observed in cases of superficial keratitis, andjw£fileding under irri¬ 
tation of the corneal nerves. Ciliary pain is iiri^QKied at night and is 
influenced by atropine, while superficial pain yi&As^o cocaine. 

2. Intolerance of the Eye with Respecir-fbJtrritant Medicaments. —In 
many cases the gravity of a keratitis ia sV^rn by the ulcer extending in 
depth, or becoming strongly infected, botfie effect exhibited from the use 
of irritant remedies employed in the Treatment of the superficial forms 
of inflammation, such as seen in^Nflyctenular or granular disease. These 
agents, far from acting favo^ai^y^xaggerate the symptoms of irritation, 
such as ciliary pain and injoe^h, for an hour or more. Warning will thus 
be given to discontinue^nywritant medication, and an opportunity given to 
apply the treatment traits necessary for deep keratitis. 

3. Deep VascidQwxition of the Cornea .—Where a keratitis is compli¬ 

cated by vascukowmon of the cornea, the affection is seen to be profound 
or superficia*NJ|^ccordance with the situation of the vessels, this often being 
determined inspection when such vessels traverse a portion of the cornea 
that more or less transparent. It is especially important, in the pro- 

foimd >orms of keratitis, to examine the eyes simultaneously with the 
qjJJtHhlmoscope and with a convex lens of from eight to twenty diopters 



(see vol. ii. p. 56). Ordinary binocular vision, however, is sufficient to 
determine the level of the vessels. 


May be traced as far as the episclerotic 
ciliary vessels. 

Are easily observed. 

Subdivide like the branches of a tree, 
and are often sinuous. 

May elevate the anterior level of the 
cornea, producing a surface which is raised 
and bosselated. 


Disappear under the limbus conjunc- 

Are less discernible on account of their 

Are seldom subdivided; are parallel to 
one another. 

The corneal surface is regular, not ele¬ 
vated by the vessels, but dull. 

Other Symptoms of Keratitis.—4. Photophobia and Blepharospasm. 
Lacrymation .—Photophobia, pain caused by the impinging of light upon 
the eye, is scarcely explicable physiologically. It is known, however, that 
light does produce a painful impression, but it is impossible to explain 
satisfactorily its modus operandi . Blepharospasm, cramp of the orbicularis 
muscle, is partly a result of the photophobia and partly a reflex spasm, which 
is produced by irritation of the corneal nerves. Like dread of light, it is 
observed even in cases of superficial keratitis. 

From a knowledge of the special functions possessed by nerves, the 
phenomenon of photophobia is an extraordinary one. Evidently the sen¬ 
sory fibres of the cornea are not excited by light. It would, therefore, 
seem to follow that the impression of light upon the retina ite painful, which 
is in opposition to the theory that retinal excitation ca^Cj%uce any other 
sensation than that of light. The matter is capablc^^being understood, 
if it is admitted that the pain is not strictly conn^QKwith special afferent 
nerves, but that it results from an excessiv^efighition of any centripetal 
nerves that are present. This is probably {IrfcSfue explanation. Thus, in 
section of a non-atrophic optic nerve, t^anSject operated upon will com¬ 
plain of a sensation of light that m§^ be so severe as to be “ painful.” 
Again, traumatic luxation of the ej0all in front of the orbit produces a 
painful sensation of light which ^insupportable, the pain being somewhat 
similar to that which is observ(0wnen attempts are made to look at the sun 
with the naked eye. T\faM$ofy is, therefore, advanced that in cases of 
keratitis, accompanied ^Vphotophobia, a superficial inflammation of the 
sensory nerves of th^ccpiea provokes a hypersesthesia of the optic nerve, 
or rather of its^ c^ntrai termination, just as ordinary light gives rise to a 
painful sensatianSJphe optic-nerve apparatus. In this connection it should 
be mentione^ri^«J inflammation of the retina and of the optic nerve do not 
produce t^s^Miotophobia. 

a o^lanation of the phenomenon of blepharospasm is more com- 
ble, its purpose being to guard the hypersesthetic visual apparatus 
it, which is functionally painful to it. A different kind of spasm 
the orbicular muscle may be observed when the eye is not at all irritated. 



This condition, when not attended with pain, is known as tic non-douloureux, 
and is believed to be due to a lesion that is situated either in the facial nerve 
or in its nucleus. At other times the spasms are painful ( tie douloureux ), 
and result from an excitation of one or more branches of the trigeminus 
outside of the ocular globe, such as dental caries, or inflammation of one of 
its branches or of the Gasserian ganglion. The contractions seen in tic dou¬ 
loureux seem always to be of a reflex nature. In true blepharospasm due 
to corneal disease the spasm is provoked both through the optic nerve and 
through the corneal branches of the trigeminus. Cocaine, by anaesthesia of 
the nerves of the cornea, sometimes causes it to disappear; again, it seems 
only to diminish it. The spasm rarely disappears even in the dark. 

Reflex sneezing, which so frequently occurs in diseases of the cornea 
accompanied by blepharospasm, is likewise provoked by a combined irrita¬ 
tion of the corneal nerves and of the retina. Indeed, many persons in good 
health sneeze when they gaze at a focus of light. In corneal disease, sneezing 
is induced when the eyelids are violently opened, more especially, when they 
are held apart for some time. As the act of sneezing is not suppressed in 
the dark, it is proper to suppose that the morbid condition which incites it 
is due to the prolonged contact of the air with the cornea, which is painful 
even in the normal state. In other respects, true blepharospasm is not so 
purely a reflex phenomenon as in tic douloureux or tic non-douloureux. In 
the beginning, at least, the contractions of the orbicularis muscle are more 
or less intentional, being designed to relieve the photophobia. Even in the 
later stages the will is able to moderate them. As opposed to tic non-dou¬ 
loureux , blepharospasm must, therefore, be regarded as hal^Wuutary and 
half reflex, and an act which is always more or less UHjJN^the control of 
the will. Horner has maintained that blepharospasmAj^xclusively caused 
by the patient remaining in the dark, and states /tfyt twitching does not 
appear if they are forced to live in weU-ilhimi*Swea places from the time 
of the beginning of the disease. This opi|?u)^^f Horner is too dogmatic, 
although the writer does not deny that l|yiiig - un the dark is of a nature in 
itself which tends to exaggerate any e^Jpg blepharospasm that has been 
induced by retinal hypersesthesia. 

The lacrymation, which occu^ilo frequently in cases of keratitis that 
are accompanied by pain andAjkpifltophobia, is another reflex phenomenon 
which is due to irritationotfHra sensory nerves of the cornea: the flow of 
tears is induced by a iMe£ innervation of the sensory nerve-fibres of the 
lacrymal gland. 4 

5. Visual Disorders .—When an eye is first affected by a keratitis it 
quickly becomesjffi^fgued. Should corneal alteration or cellular infiltration 
and oedema^S^ar and extend in front of the pupil, visual acuity will be 
diminished. or the mechanism of this form of disturbance of vision see 
chapt^p^^ Maculce Cornece.) 

pi^famsion of the Eye .—In moderately extensive keratitis, which has in- 
jppyirboth the epithelium and the endothelium, intra-ocular tension becomes 




reduced, for the reason that elevation of the endothelium particularly favors 
filtration of the aqueous humor through the corneal tissues. Intra-ocular 
tension becomes nearly abolished whenever an ulcer has perforated the 

7. Sensibility of the Cornea .—This condition, tested by means of a fila¬ 
ment of cotton, may be diminished. At times this diminution is in a meas¬ 
ure dependent upon paralysis of the trigeminus, and may be either the cause 
or the effect of the corneal inflammation. In cases of extensive and severe 
keratitis, diminished sensibility of the cornea may be easily produced, and 
may coexist with ocular and periorbital pain. 



In the treatment of keratitis the primary object, although a negative 
one, is to avoid irritating the cornea, as corneal diseases generally are aggra¬ 
vated by irritants, and subside when irritating influences are removed. This 
is one of the most important principles in the treatment of diseases of the 

A frequent cause of irritation lies in the use of medicinal substances 
(ointments, collyria, etc.) which the physician is but too often tempted to 
apply to the surface of an eye that is affected with keratitis, especially when 
the inflammation is accompanied by a secretion. As a general rule, such 
drugs should be employed only in exceptional cases, which will be duly 

1. Dressings of the Eye: the Occlusive and Compress Bondage. —A com¬ 
mon cause of mechanical irritation is the act of winkii^xjty rubbing the 
affected parts, which, as a rule, are more or less ulcers^^y the eyelid irritates 
them and disturbs the histological processes of restoration. For the same 
reason that ulcers of the skin should be covejje^pli a piece of plaster the 
affected cornea should be protected against^Efi^i’ubbing of the eyelid, and 
this cannot be better done than by an fcccAiSive bandage. It is therefore 
necessary to immobilize the eyelids well-applied bandage. This can 
be done so as to exert a certain a^^unt of pressure on them, especially 
towards the nose, on a level witl^^ie tendon of the orbicularis muscle, by a 
padding made of some elastCjmaterial, such as cotton. To render the 
bandage more absorbent^lftfe tears, conjunctival secretions, etc., a pad of 
gauze should be placgd/>w^ the eye, the periorbital hollows being filled in 
by cotton that is hel^accurately in place by the bandage. It is not neces¬ 
sary to employ 4 tl^so-called antiseptic cotton and gauze; scoured cotton is 
sufficiently asopfita^r it and the gauze can be rendered so by steaming. 
Impregnafi^^r both cotton and gauze with antiseptic liquids impairs the 
absorb^dQ^Ver of the dressing. In fact, a non-aseptic but absorbent 
dressingS^of greater value than an antiseptic but non-absorbent bandage. 
^^\ere perforation of an ulcer is threatened, or when it has actually 
>oc<Wred, the bandage should be applied more tightly, so as to compress the 
. The bandage should be renewed at least daily, and even more fre- 



quently if there is any lacrymal or conjunctival secretion, especially of the 
muco-purulent type, which when retained in the eye becomes a culture 
medium for bacteria. If the conjunctival secretion is very profuse, as in 
the blennorrhoeic and diphtheritic forms of conjunctivitis, or when there 
are exuberant granulations, bandages may be harmful; the conjunctival 
disease is then usually the cause of the keratitis. Bandages, however, are 
useful when the conjunctival secretion, even though slightly purulent, is a 
consequence of an ulcerous or a suppurative form of corneal inflammation. 
Finally, there are cases of simple keratitis in which the bandage is harmful, 
or at least it is useless ; these exceptions will be described later on. 

The bandage often acts as a preventive for the entrance of dust parti¬ 
cles, whether they be infected or not. Normally, by collecting such foreign 
substances on the free borders of the eyelids and by driving them towards 
the lacrymal ducts, the movements of the eyelids are sufficient to expel 
them from the polished surface of the cornea. Such is not the case, how¬ 
ever, when the corneal surface is roughened and ulcerated; the particles of 
dust, microbes, etc., collecting in the depressions and on the borders of the 
eyelids cannot be removed by the act of winking. In keratitis, the move¬ 
ment of the upper lid is like that of a pencil loaded with a culture of some 
pathogenic microbe by which the cornea becomes inoculated. From this it 
can be understood that immobilization of the upper lid by a bandage is the 
means, par excellence , for avoiding infection of the cornea from any irregu¬ 
larities of its surface, as well as for the purpose of maintaining cleanliness. 

2. Antiseptics .—Most cases of keratitis are infected or are liable to be¬ 
come so through even the slightest break in the epitheliiufoA Hence it is 
always necessary to employ antiseptic measures,—that is^rOhse well-devised 
means of cleanliness. It is necessary to cleanse tli^Jrghly by means of 
antiseptic solutions, not only the surface of the coi»*p*r and the conjunctival 
sac, but also, and above all, the free edge of th^^elids (that receptacle for 
microbes) and the surrounding skin. WhytT^^lute asepsis of the surface 
of the eye is impossible, the number of ifoictaces may be so diminished that 
they are unable to exert any injurious ©V thus allowing the bactericidal 
properties of the tissues to acquire i&e mastery over them. 

In healing this condition var^^“antiseptics are employed, but, unfortu¬ 
nately, two of the best of tl^s^^imoolic acid and nitrate of silver—are too 
irritating to be of any valinrh^the treatment of keratitis. Preference should, 
therefore, be given to fthgcnoice of those antiseptics that possess as few 
irritating properties gs possible. The best of these are the soluble salts of 
mercury, which areAi^st often employed in the form of an aqueous solution of 
the bichloride strength of 1 to 2000, 1 to 5000, and best 1 to 10,000. 
In using t^^^mution the ocular surface of the conjunctival sac should be 
flooded dry bandage applied. In the case of deeply infected ulcers, 

CompUSA wet with a solution of 1 to 5000 can be placed over the eye, the 
ac&mVf the drug in this strength being less intense but more lasting, 
tde of mercury in aqueous solution of 1 to 5000 is said to be less irri- 



tating (Cliibret). Biniodide of mercury in the proportion of 1 to 20,000 
is also employed (Panas). Iodoform in powder, followed by the use of a 
bandage, is less energetic, but its action is more enduring, diminishing the 
conjunctival secretion, particularly in cases of infected ulcers. This drug 
acts as an irritant to an eye that has just been flushed with bichloride of 
mercury solution, forming therewith an iodide of mercury. In some cases 
pyoktanin may be recommended as an antiseptic of value (Stilling). This 
drug appears in the form of different aniline colors, the methyl blue being 
the one that is preferred. It should be applied as an aqueous solution 
varying in strength from 1 to 1000 to 1 to 10,000. Methyl blue may also 
be used in the form of a crayon, with which the ulcer can be touched after 
cocainization. The tincture of iodine applied with a camePs-hair brush 
to the ulcers could be employed to advantage, were it not for the extreme 
pain arising from its use, even in those cases in which previous cocainiza¬ 
tion of the eye has been practised. Chlorine water has also been recom¬ 
mended for the treatment of this condition. Applications of protargol do 
not seem to be attended with the same beneficial results as when they are 
used in blennorrhoeic conjunctivitis. Under keratitis reference will be made 
to the use of subconjunctival injections of the salts of mercury and of the 
cyanide of potassium. 

3. Cauterization .—The actual cautery has been brought into general use 
chiefly by Gayet, and at the present time is employed in the form of the 
galvano-eautery. See Yol. III. of this System, p. 823. It is efficacious 
in the treatment of infiltrations and infected progressive ulcers, even when 
there is hypopyon; it destroys the most intense varietie^Acorneal infil¬ 
tration and the nests of microbes, while other complicaijSta, such as oedema 
of the cornea, iritis, and hypopyon, that are ordinawQvne effects of remote 
microbic action, improve rapidly under this fora^otreatment. 

4. Mydnatics .—Sulphate of atropine is empuSf ed in the form of collyria 

of one or two per cent, strength, made a^popvy the addition of corrosive 
sublimate. It is a remedy of great u^lit^n many cases of keratitis, its 
use being indicated whenever there isQJ)iiritis or even a congestion of the 
iris. By dilating the pupil, it cqtftyacts the vessels of the iris, and thus 
has practically an antiphlogisti<Qj5ect, while ciliary pain subsides as soon 
as dilatation commences. AmAarily, the corneal inflammation itself im¬ 
proves rapidly, leadin^irflyto suppose that the drug acts favorably on the 
corneal lesion also. r Jyhi^l 10wever ? does not seem to be the case, although 
it is doubtless trye£fchat any congestion of the iris acts unfavorably on a 
keratitis. A siij^fevarop of atropine dilates the normal pupil, but when 
there is conge^l^n of the iris repeated instillations (made by the physician 
himself) necessary, the attendant maintaining any mydriasis that 

may ha\re T^en secured by the medical adviser. In order to secure good 
resu^te^i^ often becomes necessary to make frequently repeated instilla- 

i(^s.^Application of contaminated atropine may produce pain, which, 
bver, may be promptly relieved by the use of a drop or two of cocaine. 




Daring the instillation the canaliculi should be compressed, and care should 
be taken not to drop any of the drug into the mouth. When the drops are 
properly introduced into the eye atropine-poisoning is not greatly to be 
feared, for at most, in such cases, a mere painful dryness of the throat 

In children, however, the most careful instillation of even one or two 
drops may, by mere resorption into the conjunctival sac and the lacrymal 
ducts, produce some symptoms of poisoning, notably great congestion of 
the face, which is sometimes followed by elevation of temperature. Finally, 
certain adults are so susceptible to the action of this drug that the instilla¬ 
tion of two or, at most, three drops is sufficient to produce very evident 
symptoms of general intoxication. In such cases scopolamine may be em¬ 
ployed. Its mydriatic effect is very pronounced, and proves almost as last¬ 
ing, on the whole, as that of atropine. 

Atropine is uncalled for and fails to afford any marked relief to any 
pain which is caused by a superficial form of keratitis, and which is local 
and unassociated with ciliary neuralgia. In such cases the drug needlessly 
augments the photophobia, allowing more light to enter the eye. It is con¬ 
traindicated when dilatation of the pupil is impossible and in cases in which 
there are severe hypopyon and iritis, or in which firm, old, anterior or pos¬ 
terior synechia are present. In such instances it produces an increase of 
ciliary pain and gives rise to a tendency for the eyeball to became hard. 
In deep ulcers it augments the danger of perforation by increasing the 
pressure in the anterior chamber and by paralyzing the intra-ocular muscles. 
(See article on j 1 of atropine 

is not sufficient to dilate the pupil, it is better to aband>$jKit^ employment 
and even replace it by the use of eserine. PerijdieraJ^jpblapses of the iris 
are aggravated by the employment of atropine. iQwiatropine has a very 
feeble and quite transient action in corneal inflammation. 

pupil, it is better to aband>$jXit^ employment 
le of eserine. Peripherayjpblapses of the iris 

of atropine. lOmatropine has a very 

5. Miotics .—In keratitis, miotics dimiidsW^e tension of the eye, thus 
possessing an opposite effect to that which ^^>served from the employment 
of mydriatics. By their use the intraocular muscles are contracted and 
the irido-corneal angle is freed. (SeWirticle on Miotics.) Eserine may 
often be employed with good effqSwJin ulcerations or in softenings of the 
cornea and for the preventioii^r^ireatened ectasis or perforation. It is 
also used for the purpose Q^^cfucing any peripheral prolapse of the iris. 
It can be employed in/ffi(Incases in which it is desired to overcome any 
increase in the ocular tension that may have been caused by atropine. Its 
usefulness in certam'lJXms of keratitis has led to its more or less general 
employment iivJl^varieties of corneal affection, thus exceeding its scope, 

niotics dimiiusW^e tension of the eye, thus 
that which served from the employment 
the intraocular muscles are contracted and 

d. j^ec'-article on Miotics.) Eserine may 
efWwJin ulcerations or in softenings of the 

reatened ectasis or perforation. It is 

^aucing any peripheral prolapse of the iris, 
'cases in which it is desired to overcome any 

employment nwjUAarieties ot corneal affection, thus exceeding its scope, 
which shou^M^to employ it only in well selected cases. Eserine certainly 
possesses n^eal antiseptic properties. One or more drops of a one or two 



6. Cocaine .—This drug, which was brought forward by Roller, if used 
in the form of an aqueous solution in the strengths of four to five per cent., 
quiets for some fifteen minutes to half an hour the so-called “ superficial 
pains,” and renders the cornea insensible to painful applications, such as 
caused by the employment of the thermo-cautery and the crayon of methyl- 
blue. Its utility is incontestable in pronounced cases of irritable superficial 
keratitis, but it can be scarcely considered adequate as an exclusive treat¬ 
ment in this condition, while its abuse may lead to exfoliation of the epi¬ 
thelium and insensibility of the cornea, in themselves a cause of keratitis. 
Poisoning from its use is not to be feared. 

7. Narcotics. —With the exception of hypodermatic injections of mor¬ 
phine, narcotics have but little effect in relieving the pain of keratitis. The 
remedy for the superficial form of pain is cocaine, while that for the ciliary 
variety is atropine. In cases in which the latter drug does not have the 
desired effect, a sedative action may be frequently obtained from the internal 
administration of antipyrin or phenacetin, in doses of twenty-five to fifty 
centigrammes, given in the form of powder, which may have to be re¬ 
peated once or twice at half-hour intervals. 

8. Dark Glasses and Shades .—The eyes of patients suffering from photo¬ 
phobia and blepharospasm should be more or less protected from light by 
means of card board shades and spectacles with very large (shell-shaped) 
glasses of some dark color. Smoked glasses are to be preferred to blue ones, 
as the blue rays irritate the retina. The selection of such glasses should 
not be left with the patient, as he is likely to secure too light a tint. By 
wearing such coverings to the eyes pain is lessened and th^natient is able 
to go out of doors for the purpose of exercise. 

9. Revulsives and Local Abstraction of Blood.—&y*n\lsives and living 
or artificial leeches applied to the temple are of^Wr little use in keratitis 
unless the condition be complicated by an iridq^ditis. 


A rational division of the differe^^fcrms of keratitis is impossible in 
the present state of knowledge, especially as there are not any means of 
subdividing them according to^foSfxed basis,—such as, for example, an 
anatomical one. 

Nevertheless, a fundai/enljltTlivision of the different forms of keratitis, which is useful 
from a clinical point of vi^p^is that into a superficial and a deep variety. The clinical 
characteristics are difl^Gjin each, necessitating appropriate methods of treatment. These 
differences are base^T^Vgely upon anatomical grounds. The anterior corneal planes (the 
conjunctival ppi^p^of the cornea) receive their nutrition in almost the same manner as 
the bulbar c^N^^tiva, while the deep planes have a nutriment supply that is more closely 
allied to thaOfcihe sclerotic, the iris, and the ciliary body. The anterior corneal planes are 
chiefly ^cVrished by an anastomosis of the conjunctival vessels with those of the superficial 
ciliaftj/toss^ls, while the deep ones receive their nutriment from the deep ciliary vessels. 
TJte anterior planes are enervated upon the periphery of the cornea by superficial nerves, 
elsewhere they are supplied by deep posterior ciliary branches that arise from the 



ciliary body. From an embryological point of view, the superficial corneal planes belong 
to the conjunctiva ; the middle are derived from the mesoderm,—a part of the sclerotic, 
and the deeper planes appear to be reflected from the primary optic vesicle, just as in the 
case of the chorioid, the ciliary body, and the iris. 

Certain disorders are to be found indifferently in the limbus conjunctive and in the 
anterior corneal planes (such as phlyctenular and superficial punctate keratitis). Most 
of the conjunctival maladies which invade the cornea primarily produce a superficial form 
of keratitis (such as granular pannus). The superficial varieties of inflammation of the 
cornea, rather than the deep ones, are accompanied by a congestion of the conjunctival 
vessels, while deep disorders involving the cornea, the iris, and the ciliary body bear an 
important relation to one another. In the superficial forms of inflammation of the 
cornea the newly created vascular channels originate from the superficial pericorneal vessels, 
while in deep keratitis the blood-supply is renewed from vessels that anastomose with 
those of the deeper trunks. The development of the deep primary disorders, which are 
often, if not always, of constitutional origin, as from syphilis, rheumatism, etc., takes place 
with extreme slowness. On the other hand, the superficial forms of inflammation are of 
comparatively rapid formation, and are rather due to traumatic causes or to ectogenous 
invasion by bacteria. 

Another division of keratitis is into a bacterial and a non-bacterial form, in which 
suppuration, corneal infiltration, and ulceration are to be considered. 

The variety of the lesion is sometimes sufficient to justify a distinction. Again, cases 
resembling each other clinically may exhibit an etiological difference. 

The study of the varieties of keratitis may be arranged under the fol¬ 
lowing heads: 

A. Superficial keratitis, which is further subdivided in accordance with 
its etiology, the form of the lesion, source, etc. 

B. Deep corneal inflammations that are (a) due to bacteria and sup¬ 

purative ; ( b) non-suppurative and non-ulcerous, which cojAist essentially 
of infiltrations. . ^ 

0. Cicatricial secpielse of keratitis. 

D. Corneal tumors. 

These subdivisions are defective in more thaij^j© respect. A superficial 
keratitis may start as such, but later, owj^gQ)) its extension, it may be 
necessary to class it with the deep varietj^Jjr the inflammation may be 
deep, and yet, owing to certain analo<g&^ as to its origin, will have to be 
placed with the superficial varieties, AJIeratitis by becoming infected may 
totally change its clinical course. 


a.— su: 


In this variety of ^/enrH-ns the anterior corneal planes, the membrane 
of Bowman, and oftgn^tne adjacent corneal lamellae are involved. An 
infiltration, which is^ometimes vesicular, usually gives rise to a deposit 
that projects bowtA the surface and which in turn is followed by ulcera¬ 
tion and los^Qfcubstance. It is possible, however, for the erosion to be 
primary, r^ter, the new formation of corneal blood-vessels may play an 
importa^^'d/c in the development of pannus.—The general symptoms of 
keRatrPi^ consist in disturbances of the cornea, roughening of the corneal 
stt^^e, absence of lustre, superficial ulcers, and ciliary injection. The seat 



and extent of the lesion producing a general or partial ciliary injection is 

generally associated with a slight conjunctival injection. When blood¬ 
vessels are formed within the cornea, under Bowman’s membrane, the 
epithelium is, as a rule, elevated by them, and they can be traced as far as 
the superficial ciliary vessels. Pain may be absent or be only of a minor 
character. The occurrence of ciliary neuralgia and contraction of the pupil 
should always awaken the suspicion that the affection has gained in depth 
and has become infected. The degree of unevenness of the surface naturally 
varies from roughness that is barely perceptible to one in which the eleva¬ 
tions and depressions are plainly to be seen. A deep infiltration is one 
which is more apt to be diffuse, not so raised above the surface, and more 
tardy in becoming ulcerated. 

Prognosis, as a rule, is favorable unless a severe secondary infection— 
which is always to be dreaded—supervenes. The amount of visual dis¬ 
turbance depends on the location of the trouble in relation to the pupil, 
and on its extent and character. The usual treatment is that which is 
indicated for superficial traumatic keratitis. 


Traumatic injuries to the cornea may be caused in the most diverse 
ways (see Corneal Ulcers); they may arise from external conditions, 
whether produced by the person himself or by other agencies, or they 
may originate within the protecting structures of the eye. A simple wound 

of the cornea usually heals : - 1 - xl " ' J 1 1 deserve to be 

called a keratitis. To con se the injury 

must be followed by micro ■ the trauma¬ 
tism is rarely sufficient for t tervention of 

microbes plays a hading rdh 

As external causes for traumatism solid juM^es floating in the air, rain, 
snow, wind, rubbing with the hand, detadi^N^dies from larger objects, etc., 
may be cited. Disappearance of the ey«-lMi*es naturally permits such objects 
more readily to gain access to the corr&b. Within the structures normally 
used for protecting the eyes from ioiuty, swellings and cicatrices of the con¬ 
junctiva, various conditions lids, deviated cilia, and crusts on the 

palpebral borders may be fo^tVThe lids may be deformed by congenital 
conditions, by traumatisna^Mby various affections, such as blepharitis and 
cicatrices of the neigtffformg skin, and in consequence no longer adequately 
protect the € n i^ncies that ordinarily would not prove detrimental 
to the corner , the eye so affected remains partly open during sleep, 

and thus can il desiccation and exfoliation. Anaesthetics, whether 

+ * 

local or 7 paralysis of the trigeminus act in the same way. 

local or 7 paralysis of the trigeminus act in the same way. 

Diseases xhich lower general sensibility, as typhoid fever, must be included 

ted through agencies of the most varied 

of infection operate so frequently that 



they seem to induce keratitis alone without traumatism. Causes of infection 
are blepharitis, affections of the lacrymal passages or of the mucous mem¬ 
brane of the nose (ozsena), facial eruptions, etc.; more often than is gener¬ 
ally supposed the infective germs are conveyed by the hands or on a 

The symptoms observed are, generally speaking, those of the superficial 
forms of keratitis (see supra) and especially ulcers. Corneal vasculariza¬ 
tion rarely produces pannus, nor are well-marked maculae to be feared 
unless the inflammation continues for a long period of time. 

Complications .—Superficial forms of inflammation frequently give rise 
to the production of the deep variety of keratitis, this being especially true 
if the infection is of a virulent character. 

Treatment. —The proper treatment consists in the removal of the ex¬ 
citing cause of the injury, if this be possible, and of the use of antiseptic 
lotions to the conjunctiva and the tarsal margins, for it is in these situations 
that bacteria find a favorable nidus for their multiplication. The applica¬ 
tion of a bandage is here of importance. Should affections of the lacrymal 
passages, blepharitis, cutaneous eruptions, or ozsena exist, they should re¬ 
ceive appropriate treatment Yellow oxide of mercury ointment and other 
remedial agents employed in vascularized phlyctenules are of value in stimu¬ 
lating rebellious ulcers in which cicatrization and a fillino; of the excavation 
consist only in the corneal facet being covered with epithelium which gives 
rise to irregular reflections. Cure is often hastened by the scraping of 
affected areas with a curette. Peritomy may be employed in those cases in 
which an excessive vascularization does not yield to other m£^pds of treat¬ 
ment. (See Granular Pannus .) 


Phlyctenular keratitis (phlyctenular, lymphSiJ^or scrofulous conjunc¬ 
tivitis) is a disease affecting the corneal andfpJ^gorneal conjunctive of in¬ 
fants and adolescents. While the corn g£l hm limbus conjunctive are the 
most frequent localities in which it is it is sometimes, nevertheless, 
described among the conjunctival disuses under the name of pustular con¬ 
junctivitis, for the reason that tteNfesion is often situated on the bulbar 
conjunctiva. Conjunctival may precede, accompany, or follow 

corneal phlyctenules. /vv 

Small opacities and jfrottroerant infiltrations, that are improperly called 
phlyctenules, are found to occur, isolated or multiple, on the cornea and 
limbus conjunctive*X^rdinarily, the infiltrations ulcerate and cicatrize, but 
successive erupthfr^of phlyctenules may be accompanied by such persistent 
vascular iza it the malady lasts for a much longer time; such vascular 

forms wh<m |tfonounced constitute the so-called scrofulous pannus. The 
appeam«?^)f these eruptions is accompanied by ciliary and conjunctival 
injep^nf and is followed by photophobia, lacrymation without mucus, and 

/IV Vol. IV.—13 



Avascular Forms .—(a) In this variety a single phlyctenule, which is usu¬ 
ally of a small size and is often discovered with difficulty after ulceration 
has taken place, appears at or near the centre of the cornea. This is sur¬ 
rounded by simple ciliary injection. There is a slight degree of contrac¬ 
tion of the pupil, and frequently intense photophobia and blepharospasm 
are found. (6) Here one or several phlyctenules, that frequently show vas¬ 
cularization after ulceration, appear on the periphery of the cornea. Ciliary 
and conjunctival injection is very marked at the level of the ulcerations, * 
and, if partial, appears in the form of a triangle with its apex turned to¬ 
wards the phlyctenule of the cornea, (c) In this form the phlyctenules are 
found in the limbus conjunctive. They may be discrete, or exhibit them¬ 
selves in the form of strings, causing the conjunctiva to swell and to con¬ 
stitute a pericorneal cushion for the ulcer. As a rule, the conjunctival 
injection is so intense that it masks the ciliary injection, (d) Although 
not avascular, the conjunctival phlyctenules, or pustulous conjunctivitis, 
may be included here. One or at most two infiltrations appear within a 
radius of half a centimetre around the periphery of the cornea. In this 
subdivision the size of the phlyctenule is larger, this being so because it 
occurs in a tissue of looser texture. 

In the same subject may be seen successively or simultaneously the dif¬ 
ferent manifestations of the various avascular forms of superficial keratitis 
just described. 

Vascular Forms. —Here the peripheral phlyctenules are especially prone 
to undergo vascular changes. The newly formed vessels arfe superficial, and 
are situated close to Bowman’s membrane, though they^r^ n$ver found situ¬ 
ated under the epithelium. The corneal surface is <^j T ated by the inflam¬ 
matory vascular channels, the course of which carfH^traced to their origin 
from the ciliary vessels. The appearance of< S'0 > Vessels in the superficial 
forms of inflammation of the cornea causes^flyWisorder to last longer than 
it otherwise would, whereas when the vresets mre found in deep ulcerations 
their presence is favorable to the repd^ofihe parts that are affected. 

Two vascular forms are to be distinguished. (a) In 'phlyctenular pan- 
nus the phlyctenules may be ui m by the formation of new blood-vessels. 
They ulcerate, but show noJ^^osition to heal. Exfoliation of the epi¬ 
thelium takes place on tiio ed^e of the persistent vessels. This process is 
followed by the appp of a new crop of phlyctenules which undergo 

similar changes. Ii^hjs manner segments of the cornea or even the entire 
membrane may^bg^me infiltrated, causing the surface to become bosselated 
and traversed In numerous blood-vessels. This variety of pannus scarcely 
ever attams^h^n a degree of development as is observed in extreme exam¬ 
ples of^^^ranular form. (6) In band-shaped keratitis vascularization of 
a relati^y large peripheral phlyctenule, which extends little by little 
t^a^w the centre of the cornea, fakes place. Behind the phlyctenule are 
ioV seen strings of blood-vessels which run almost parallel to one an- 
►Vlher to the margin of the ulcer. These vessels have the appearance of 




pushing the ulcer in the direction of the corneal centre or of being dragged 
by it. 

Pathological Anatomy .—The term phlyctenule, which denotes a blister, 
is badly chosen, as the vesicles rarely contain liquid and when they do, 
the contents are generally turbid. These cellular infiltrations are situated 
in the superficial layers of the true corneal tissue, elevating and perforating 
Bowman’s membrane and its epithelium. Even phlyctenules of small 
size, consisting of subepithelial cellular infiltrations, reach the outer layers 
of the cornea by nerve-channels (Ivanoff). Other authors could not find 
any relation between the infiltration and the nerve-canals. (Fig. 7.) While 
the infiltration may be very deep at the onset, the invasion of the deeper 
corneal planes is more often the result of a late intense infection by bacteria. 

The newly formed blood-vessels are found to be situated beneath Bow¬ 
man’s membrane. 

The anatomical details of band-shaped keratitis are but imperfectly 

Etiology .—Lymphatism and scrofula are predisposing causes for the 
production of phlyctenules, which, as a rule, appear simultaneously in 
both eyes. These conditions may not be manifest at first, but the long 
duration of the disease gives rise to anaemia and lymphatism. The coryza 
and the swelling of the upper 

lip, which are often cited as * IG * 

proofs of a lymphatic state, 
may be directly consequent 
upon the ocular disorder, 
without which they would 
not occur. When once estab¬ 
lished the phlyctenular dis¬ 
ease is kept up by the coryza, 
the septic secretion being con¬ 
veyed to the eyes by the 
hands or handkerchiefs. In 
some exceedingly rebellious 
cases adenoid vegetations may ^ 
be found in the throat, an^^£$ 
their extirpation is folhiv^ti^ 

by rapid healing of the^jjta. The enlargement of the submaxillary glands 
is frequently a cousqgjaence of facial eczema, which may have resulted from 
irritation of the by the secretions arising from the affected eye. On 
the other hand^Qke eczema may have appeared first, or have become promi¬ 
nent simu&^$busly with the outbreak of the phlyctenules, in which case 
they mayvb^looked upon as eczematous in type. 

A^THa!^ already been stated, phlyctenules are frequently situated on the 
lir^ns^conjunctivae; they are accompanied by intense conjunctival hyper- 
and a secretion of mucus, the so-called eczematous conjunctivitis of 

Subej^^lial cellular infiltration in a vesicle of phlyc- 
' 1 "“ keratitis (after Ivanoff). 

ithelium; b, Bowman’s membrane; c, corneal 
d, subepithelial cellular infiltration ; e, nerve-canal, 
! h which the migratory cells have reached the 



Horner. At other times the conjunctival inflammation is secondary to the 
phlyctenules and is the result of their improper treatment. 

This form of conjunctivitis is the most common ocular disease of child¬ 
hood, and is essentially a malady of the early years of life. It is rarely 
found before the first year, appearing most frequently from the fifth to the 
twelfth. The condition is rarely seen after the age of twenty-five years. 
It must be stated that in children injuries or other causes of keratitis have 
a strong tendency to appear under the form of lymphatic cellular infiltra¬ 

The ordinary microbes of suppuration are found in the affected areas 
(Gifford), and, on the authority of Bach, staphylococci are always to be 
obtained from the small areas, provided that the examination be made on 
the first or the second day. As this same variety of organism is found 
also in eczematous eruptions, the relationship which is said by Horner to 
exist between the phlyctenules and eczema would be thereby confirmed. 

Course and Symptoms .—There is no disease of the eyes in which photo¬ 
phobia and blepharospasm play a more important part than they do in 
phlyctenules. This seems to be due to the numerous superficial nervous 
filaments becoming distended and compressed, either in the epithelium cov¬ 
ering the cornea or in their passage through the membrane of Bowman.— 
An eruption of phlyctenules may heal with considerable rapidity. Ordi¬ 
narily, however, there is a marked tendency for relapses to occur, fresh 
eruptions following one another in rapid succession or appearing after the 
lapse of variable periods of time. In obstinate cases, it is pitiable sight to 
see the affected children shrinking for weeks and montj^rcln daylight by 
various devices, such as seeking dark corners and b^^mg their heads in 
cushions. The lack of air and of light lowers tl^^hneral nutrition, and 
produces anaemia and lymphatism, if these comjU^^is do not pre-exist. The 
tears, which normally possess an alkaline are often mingled with the 

irritating secretions from the eye, and t{us)procluce a conjunctivitis which 
is sometimes purulent. Excoriations^^ the skin of the lower lids, fissures 
at the external palpebral angles, contaj and swelling of the upper lip may 
occur. Persistent blepharospasd^ads to an oedematous swelling of the 
upper lid, which later may to the lower one. The brows are con¬ 

tracted by the spasm of tl^^rs, and the eyelids are closed for the purpose 
of shielding the eyes i IS 0^11 as possible from the light. 

Complications .—the infection is intense, it may produce suppura¬ 
tion ; or a small fijneal phlyctenule, which can be discovered only with 
difficulty, owin^xb the intense involvement of the cornea, may appear as 
the point iff^rkrance for the production of a profuse deep keratitis (paren- 
chymatc^A^L'atitis). Such a condition is made manifest by intense ciliary 
pain, contraction of the pupil, and an intolerance to the employment of 
orStffar^ medications. Perforation is often produced by peripheral phlyc- 
Jfemues. Conjunctival catarrh may be simulated by a copious secretion from 
•ftlb conjunctiva. It is well to remember in this connection that simple 



(non-follicular) catarrh is nearly unknown from the fifth to the twelfth 
year, the time at which this affection is most likely to be observed. 
Blepharitis, which is likewise an expression of lymphatism, and usually, 

a cause of phlyctenules. 

Prognosis .—This is favorable, unless infectious complications supervene, 
the latter too often being the result of negligence. Minute ulcers heal 

without leaving an appreciable macula. Dense, permanent maculae are 
ordinarily the result of large phlyctenules, especially if they have assumed 

the vascular variety. The track of band-shaped keratitis can always be 
traced by the resultant opacities. 

Treatment .—As this condition is often due to a general cachexia as well 

as to local causes, treatment must usually be directed to both of these con¬ 
ditions.—Local measures alone are sometimes efficacious, and should vary 
according to the clinical forms which are assumed and the complications 
that are present. Finely powdered calomel applied once daily with a dry 
hair-pencil is a sovereign remedy in simple non-vascular phlyctenules that 
are unaccompanied by conjunctival secretion. The chemical composition of 
the mercurous chloride (calomel) is gradually converted by contact with the 
secretions of the eye into mercuric chloride (corrosive sublimate). Care 
must be exercised not to use too great a quantity of calomel, as it accumu¬ 
lates in the inferior cul-de-sac and acts as a caustic on the conjunctiva. 
The simultaneous use of the iodides internally and calomel locally is contra¬ 
indicated, as the former drug appears in the lacrymal secretions and con¬ 
verts the calomel into the iodide of mercury, which act^j#tf| irritant.— 
The mild chloride of mercury is of no value in the trea^Jpft of phlycten¬ 
ular pannus, and is especially useless in band-shaped-flpratitis. Here the 
ointment of the yellow oxide of mercury exerts ^yVost beneficial action, 
particularly if the conjunctival secretion isz-SSfe abundant. A small 
amount of the ointment, prepared in the/pap^tion of one-half to one 
centigramme or more of the yellow oxitfe oP^mercury to one gramme of 
vaseline, should be placed daily on the of the eyelids and distributed 

over the eyeball by gentle massag(0pade through the upper lid.—The 
applications of calomel and of yellow oxide of mercury ointment 
should be made by the physi^fo^imself. For continuous use lotions of 
the bichloride of mercury n^aybe prescribed. Conjunctival secretions and 
eczematous forms of th^cHsease should be treated with weak astringents, 
such as boric acid Jqfcjons, and antiseptics, such as solutions of corrosive 
sublimate. After il^gecretion has been diminished by these methods re¬ 
course may be^l^Vro the use of calomel and the yellow oxide of mercury. 
—Atropi nout effect in lessening photophobia and blepharospasm. 
The lalteu cNnclition may be made to disappear temporarily by the pro- 
ducti(^v^*\[ight asphyxiation. This barbarous method of relief is secured 
l Ting the child’s nose, the face being plunged for a brief period of 

t a water.—The wearing of dark glasses and of a visor are often 



helpful. Prolonged application of cocaine is sometimes of value.—Ex¬ 
perience has shown that the wearing of a bandage is not only useless, but 
that it often acts unfavorably, even in cases in which the secretions are 
not copious. It ma^, however, be of value in those cases in which it is 
desired to prevent infection of the eye from excoriations of the skin and 
coryza.—Facial eczema, nasal catarrh, and any cause of special infection 
demand appropriate treatment. For the eczema the ointment of the oxide 
of zinc may be employed. The coryza may be lessened by the use of 
sufficiently strong ointments of the oxide of mercury, or by insufflations 
of powders containing equal parts of bismuth, boracic acid, and camphor. 
In this condition astringent injections are of use. If in rebellious cases 
adenoid vegetations of the pharynx be found, their extirpation is the 
necessary and very efficacious treatment. The fissures of the external 
angles may be touched by a crayon of the nitrate of silver.—For simple 
phlyctsenulae daily instillations of eserine have been recommended by 
certain authors. The drug, however, is badly tolerated, and its efficacy is 
doubtful.—In band-shaped keratitis cauterization of the ulcer by heat is 
ordinarily superfluous. If the ointment of the yellow oxide of mercury 
does not suffice in effecting a cure, curetting of the ulcer by means of a 
Daviel spoon appears often to be valuable in shortening the duration of 
the affection (de Wecker). Peritomy is superfluous, unless it is employed 
in the rebellious forms.—It is important to remember that the use of revul¬ 
sives in the treatment of the disease should not be permitted.—The severe 
infection of a phlyctenular eruption, with penetration toi a great depth, 
contraindicates the employment of the calomel and of^(e^llow oxide of 
mercury ointment. On the contrary, the conditioning for a treatment 
that is applicable to deep ulcers,—namely, bai^^s, antiseptic lotions, 

atropine, etc. V.C/ 

General treatment is important. It sta&tfconsist in good nourish¬ 
ment, cod-liver oil (if there be scroful^Ty^b fresl1 air > frictions of the 
skin, and salt baths. 

As the conjunctival sac contini^fb be infected with pathogenic mi¬ 
crobes even when the phlyctenular eruption has disappeared, just as the 
edges of the eyelids remain ii^Mrd for a long period of time after styes, 
the necessity of continuiq Peptic treatment, especially the use of sub¬ 

limated lotions, for a cor^5brable period of time (several weeks) is important. 
Relapses are always^ojf>e feared, especially in the non-vascular forms. 


In cas^s/T^Tonjunctival granulations a superficial keratitis, which has 
a strom*^^$$ency to become vascularized, is almost always produced. 
StartingSrbm the superior corneal margins, this condition exhibits a slight 
exfoliation with moderate infiltration and the appearance of 

S urfeerous vascular branches that are derived from the superficial pericor- 
feil vessels. Marked projections are occasionally produced by the con- 



junctival vessels penetrating the diseased portions. As a rule, this form 

of keratitis may involve the superior half, or even the whole, of the cornea. 
The disturbances of the cornea and the inequalities of its surface afford 
a favorable opportunity for multiplication and enlargement of the vessels. 
In extreme cases—that is, in pannus crccssus rather than in pannus tenuis — 
the corneal surface is bosselated and fleshy, suggesting the appearance of a 
granulating wound.—The aspect first presented by this form of pannus is 
that of an epithelial exfoliation which has resulted from the friction of a 
bosselated cicatrized conjunctiva, or from deviated cilia. Vascular infiltra¬ 
tions of the anterior corneal planes, beneath Bowman’s membrane, which 
still remains intact, are seen. (Fig. 8, A.) This membrane is finally per¬ 
forated, and the epithelium is raised by the growth of the new vascularized 

Fig. 8. 

Granular pannus of the cornea. thejbdnular infiltration is seen under the wrinkled plicated 

membrane of Bowman. Towards the j\mMt has attacked and pierced this membrane, which has 
disappeared to a large extent. A^?fej)ortion of a follicle which is surrounded by a membrane-like 
structure and by a real trachorfatot^ granulation, included in the pannus tissue, can be seen. V 
represents a vessel that is surrounded by perivascular infiltration. The lower part of the epithelial 
lining, where it touches tl*e {Qanular tissue, is badly outlined. The cellular infiltration should pene¬ 
trate it more or ^ 

tissue that is^wsited beneath it. In pannus crassus (Fig. 8, G) non-vas- 
cular follicl^^ ire sometimes found in the midst of the granular tissue. 

These ar©^rue follicles, surrounded by a membrane-like substance. 

Qichptosis .—Granular pannus may be confounded with phlyctenular 

pannus (vide supra) and with certain forms of superficial (traumatic) vas- 



cular keratitis. It is only in exceptional cases that granular pannus starts 
not from the superior part of the cornea, and the examination of the 
palpebral conjunctiva will remove all doubt as to whether or not this is 
the case. 

Prognosis and Sequelae .—Granular pannus is characterized by its ex¬ 
treme persistence. If imperfectly treated, pannus crassus may last for 
years, and by its presence the sight of the affected eye may be destroyed. 
Pannus tenuis may also produce permanent maculae that disturb vision 
more greatly when they are situated in front of the pupil. The cornea, 
weakened by the cellular infiltration of the deeper structures, may yield to 
the intra-ocular pressure, the central curvature usually increasing (kera- 
tectasis). Finally, pyogenic microbes may invade the cornea, and thus 
give rise to suppuration, which takes place especially in the centre of the 
cornea, and may lead to perforation. Almost without exception, this pro¬ 
cess is followed by the appearance of anterior synechise and of corneal 
staphylomata which are due to softening of the corneal membrane. The 
suppurative processes may also invade the deeper structures of the eye and 
give rise to panophthalmitis. 

Treatment .—Mild cases of pannus are to be treated with irritants in the 
same manner as granular conjunctivitis. Ordinarily, such remedial agents 
influence favorably the course of the disease, preventing the necessity 
of other special measures. When the keratitis tends to become deep or 
infected, irritating medication is to be replaced by the use of antiseptic 
lotions and atropine. Should irritant drugs give rise to mersistent ciliary 
pain and augment the excitability of the eye, they shqtfitA also be discon¬ 
tinued. In such cases the writer has recently found/jJNw instillations of a 
two to five per cent, strength solution of protargoL^^peculiarly efficacious. 

bandage may be applied 
some instances recourse 


If the secretions be not too abundant, an occlu, 
concurrently with the application of iodoforsjx, 
may be had to eserine, and iridectomy necessary to avoid an ectasis. 

Jequirity .—The pannus sometime^ olsffppears after suppuration result¬ 
ing from a blennorrhoeic or gonorittSte inoculation. This heroic remedy 
was much used about the middheyiithe present century. In very intense 
double pannus crassus, surprhrfwly good results may be obtained from this 
form of treatment. It inw^^imvever, be borne in mind that a portion of 
the cornea which is notvw^red by the pannus may perforate, thus proba¬ 
bly leading to a seccmdaly affection of the fellow-eye. Fortunately, we now 
have in the seeds jrfjequirity a vegetable irritant which is more easily reg¬ 
ulated and lesg>Kpulsive than the blennorrhoeic material formerly used 
(de Wecker\^3Hie seeds contain an amorphous substance known as jequiri- 
tine, the^^kical composition of which is badly defined. When the seeds 
are plac^ln water (Venneman and Bruylant, Salomonsen, Sattler), this 
subg^Ace appears to develop by sprouting. It provokes a condition in the 
joi^rnctiva resembling that which is seen in purulent conjunctivitis that is 
e to the presence of bacteria. According to the latest formula, given by 



de Wecker, three to five grammes of the seeds freed from their cortex are 
powdered and macerated for three hours in one hundred grammes of water, 
which should be used cold, as heat destroys the jequiritine. The freshly 
prepared filtered liquid is applied over the conjunctiva of the everted upper 
lid, and even placed over the cornea in very intense pannus. This is done 
with a tampon of cotton. After one or two days a single application gives 
rise to a conjunctivitis, with croupous plaques resembling those that are 
seen in cases of mild blennorrhoea. The conjunctivitis so induced is inten¬ 
sified by repeated applications or may be maintained at will. If the con¬ 
ditions are favorable, the pannus disappears. 

In the application of this remedy the following indications for treatment 
should be present, otherwise the pannus may not heal and great danger to 
the cornea may be incurred: 

1. The pannus should be complete; a non-vascularized portion of the 
cornea threatens to perforate. 

2. The cornea of the second eye should be more or less vascularized 
throughout, the conjunctivitis being of a contagious character. 

3. The palpebral conjunctiva should be the seat of infiltrated granula¬ 
tions or be more or less cicatrized. When the amount of secretion is con¬ 
siderable, the jequirity should not be employed, as it excites too violent a 

Under the conditions just mentioned, jequirity is in a manner a specific 
for granular pannus, but it is not suitable, as a rule, for the treatment of 
general granular conjunctivitis. 

Certain authors favor peri to my in the treatment of rebeliAis forms of 
granular pannus. Its use is even more general in obstinm^asfs of super¬ 
ficial vascular keratitis. Some recommend that simple^Jfodions down to the 
sclerotic be made repeatedly, even advising that thj^Qhould be done daily. 
This is done with a view of bringing the ciliary Niseis into use during the 
time of repair. Others excise the conjunofcWUbound the cornea to the 
extent of half a centimetre’s distance, and etzoJ cauterize the bottom of the 
wound for the purpose of destroying th*Kciliary vessels. These are very 
painful methods of treatment, even^diottgh cocaine be used in their per¬ 
formance. The writer has never^dfeJoyed any other method than that of 
oft-repeated incisions. 

Eyes are often met with^i^Vich have been cured of their granulations, 
but in which the conjun/Rv|ws covered with cicatrices that look as though 
they were embossed. The rubbing of the eyelids produces incessant and 
ever-recurring exfoK^Jbns of the cornea. These are cases of traumatic 
keratitis which nAsf oe treated as such, special care being taken to avoid 
stimulants. ^CWly massage of the eyeball through the upper lid and the 
introductio^^v the ointment of the yellow oxide of mercury into the con- 

[ic are often the best means of treating this condition. 




1. Acne of the Cornea .—Acne of the face, nose, or cheeks may be ac¬ 

companied by eruptions on the cornea which have the appearance of small 

phlyctsenulae. These eruptions of acne of the cornea are found only in 
persons who have passed the period of adolescence. They are accompanied 
by marked redness of the edges of the eyelids, are extremely rebellious to 
treatment, and are prone to relapse. Calomel, antiseptic lotions, and the 
yellow oxide of mercury ointment have but little beneficial effect upon 

2. Febrile Herpes (Horner).—An eruption of the transparent vesicles 
frequently appears in febrile or catarrhal maladies, especially in disorders 
of the respiratory tract, such as bronchitis, pneumonia, and influenza. The 
outbreak is often seen concurrently with herpetic efflorescence on the edges 
of the nose, and is accompanied by pain, lacrymation, etc. The vesicles 
are more or less numerous, are often arranged in groups, and are not larger 
than the head of a pin. The walls of the vesicles are composed of epithe¬ 
lium and some lamellae of corneal tissue, and enclose a transparent liquid. 
When they burst, the resulting ulcer is slightly infiltrated. In the course 
of three or four weeks’ time the wound heals without leaving visible traces 
of its former presence. Relapses are greatly to be feared. If the condition 
be neglected, the ulcerated area may become infected, infiltrated, and un¬ 
dergo suppuration. Sometimes the * 1 r Jl first deeper and 

more infiltrated, this stage being the transition form toNShat of dendritic 
keratitis .—Under the name of idiopathic herpes has ba&pC^escribed a variety 
of eruption of corneal vesicles that is analogous t^^rose of febrile herpes, 
but which is not complicated either by facial hei^p^or by fever. Cases of 
this kind are usually classified under the temJ^r filamentous keratitis; in 
part they are epithelial vesicles, which withfl^onsidered under the heads of 
Vesicular Keratitis and Bullous KeraUtih 

Treatment .—This consists of anfee^tic lotions, a bandage, and atropine, 
if necessary. 

3. Zonular ( Ophthalmic) (see also special article on Herpes ).—In 

neuralgia of the trigeminusffl3i%)two, or three foci of intense infiltration 
sometimes unexpectedly aj^ear, often elevating the surface of the cornea, 
and always reaching/^cp<ain depth. Neuralgia of the ophthalmic branch, 
and especially of hsNmsal subdivision, has this effect, whether it be or be 
not accompanied^®?an eruption of herpetic pimples, herpes of the skin, of 
the foreheac k<$ be cheek, or of the nose, and by anaesthesia in the region 
of the vNow and then the affection begins with a group of small 

protub* infiltrations, which resemble an eruption of febrile herpes, and 

ing/a (swain 
bsNmsal su 

*M®?an eruption of 
2)uie cheek, or of tl 

not accompanied 
the foreheac uG 
of the ^ vN< 

soorhj^ecome confluent. Generally, the symptoms are more severe, and are 
nco^jqmnied by congestion of the iris or even by an iritis. The infiltra- 

| U1 Lllv XX iu UX v V Cii KJ V tl 11 XX 1 Llui JL 11 vJ 1 XIIX 1 L 1 tl"" 

(f^&ns develop into ulcers which tend to produce perforation and hypopyon. 



Healing takes place but slowly. Relapses are greatly to be feared as long 
as the neuralgia and insensibility of the cornea remain. The eruptions 
appear to have the same significance as those of zonular herpes of the sur¬ 
rounding skin, with which they are often associated,—i.e., they result from 
a peripheral neuritis. 1 This condition must not be confounded with the 
exfoliations that are so often observed in the inferior half of the cornea in 
cases of anaesthesia of the ophthalmic nerve, and which in their final de¬ 
velopment produce a suppurative neuroparalytic keratitis. 

Zonular herpes of the cornea always reveals the characteristics of an 
infected and ulcerating deep corneal infiltration, and as such might have 
been discussed under Deep Keratitis . 

Treatment —This comprises dilatation of the pupil with atropine, the use 
of special antiseptic measures, such as corrosive sublimate lotions, and the 
application of the crayon of methyl-blue to the ulcer. Cauterization by heat 
may be recommended. The neuralgia should receive appropriate treatment. 

4. Dendritic Keratitis; Malarial Keratitis (see special article).—This 
form of inflammation of the cornea (described by Hansen Grut, Emmert, 
Kipp, Noyes, Gillet de Grandmont, etc.) sometimes results from causes 
similar to those which produce febrile herpes of the cornea, and at other 
times the etiology is entirely different. The special form and course of the 
ulceration make it a separate clinical species. It begins by a circumscribed 
but rather intense infiltration which penetrates to a certain depth. The 
infiltration then ulcerates; the borders of the ulcer may be perpendicular 
or more or less hollowed and infiltrated. New eruptions appear around 
the ulcer, which enlarges principally in one direction, and /fc^ms a furrow 
on the corneal surface. The affected area has at first th2\Jppearance of a 
comma, but as time goes on it elongates until, finalh^4c becomes arbor¬ 
escent and ramified. Photophobia, ciliary pain, cojA^tion of the iris, and 
even iritis occur. When neglected, the ulceratiM^may suppurate and per¬ 
haps perforate the cornea, though under ]MrnjJp^care it has not this tend¬ 
ency. Its development resembles that of aN*uppurating, corroding (rodent) 
ulcer, or ulcus serpens, though its ten^wey to ulceration is less and the 
ulcer is more contracted. After heahng“rtll remaining opacities assume the 
arborescent form, which is also mgra&r less the appearance of deep keratitis. 

Etiology .—Febrile herpesM^^4?e transformed into dendritic keratitis. 
The writer has seen corneawmVyctaenulte assume this character. Kipp has 
often found this lesion a/socymed with paludic poisoning, and calls it malarial 
keratitis. Emmert luis isolated a microbe (a bacillus) which he is inclined 
to regard as the sp£$fePpathogenic factor (mycotic keratitis) ; it has not been 
found by other^AJrvers, but the very peculiar progress of the ulcer seems 
to demonstH^^kat microbes play an important role in the production of 
the conditim^ 


S^^pecial article on Eye Affections due to Graves’s Disease and Herpes Zoster, in 





3 ? 


Treatment —The treatment is the same as that for infected ulcers, in¬ 
cluding atropine, bandage, and antiseptics. The margin of the ulcer should 
be touched with a crayon of methyl-blue, and in obstinate cases it should 
be touched with a hot iron. 

5. Rodent Ulcer .—Under this name, Mooren, Fuchs, and others have 
described a rare affection of the cornea, which is similar to the grave varie¬ 
ties of dendritic keratitis, and of which I lately observed an example in a 
young man. It has, however, been seen most frequently in old people. 
A burrowing, peripheral infiltration is transformed into an ulcer with 
thickened, borders, which may become vascular and tend to cicatrize, when 
suddenly a neighboring portion of the cornea becomes infiltrated, ulcerated, 
etc. This process continues until the anterior layers (the epithelium and 
anterior lamellae of the corueal tissue) become elevated through their entire 
extent. The ulcer extends in furrows, which are larger and deeper than 
those of dendritic keratitis. The centre of the cornea may be invaded, 
finally emerging as a protuberant and transparent islet. The entire cornea 
is at last covered by a very dense leucoma, and vision is almost abolished. 
Prognosis is indeed grave when both eyes are attacked, either simulta¬ 
neously or successively ; for, as in the dendritic form of keratitis, the ulcer, 
being relatively deep, shows no marked tendency to suppurate, but only to 
destroy the superficial corneal lamellae. Hypopyon is rare. 

Treatment —Only cauterization by heat (galvano-cautery) to the infil¬ 
trated border of the ulcer seems to be adequate to arrest the progress of 
this grave affection (Fuchs). Corrosive sublimate, pyoktamn, etc., are use¬ 
ful only as adjuvants. Ectasis of the shrunken cornesus$ioq[d be combated 
by the employment of the compress bandage and es 


In persons of advanced age the eye ^p®fcnly becomes irritated and 
weeps a little; there are slight pericornc/TVj^ction, pain, and photophobia. 
On the cornea appear what seem to be ^eal^vesieles; most of them are small, 
but the largest have a diameter of f^^i one to one and a half millimetres. 
These apparent vesicles are tiny gtebules attached to a slender pedicle. The 
smallest are swept off by the ^^Kthe larger ones are transformed into fila¬ 
ments, of a millimetre oi^l0ta*Tkickness and half a centimetre or more in 
length, which hang flabhiyvover the front of the cornea. Winking raises 
the filaments, whichQnmvever, fall into place again. After some days or 
weeks there is a new eruption, which is followed by an exacerbation of the 
irritating symptoms. The affection may continue for months or even years. 
These eruj.)^5^sometimes consist of only one or two filaments; again 
there ma^S^JSdenly appear a great number, a dozen or more, of all dimen¬ 
sions. idiopathic variety of filamentary keratitis is, on the whole, a 

rmu^Oe, and has no tendency to become aggravated. Filaments similar to 
^hc^'may be present in chronic ulcers, their production ceasing as soon as 


aling of the lesion occurs. 



Fig. 9. 

Anatomy (Leber, Uhthoff, Fischer, Czermak, Nuel, and Hess).—In the 
midst of the epithelium of the cornea appear nests of clear, round cells, which 
are often polynuclear. The surround¬ 
ing cells elongate, and force these nests 
in front of the epithelial plane. An 
envelope of flattened cells, that are un¬ 
dergoing mucous metamorphosis, and a 
pedicle made up of elongated cells are 
then formed. (See Fig. 9, A.) 

The pedicle is composed of epi¬ 
thelial fibres, which are elongated into 
fibrillse, and rolled into spirals like a 
cable. This subsequently lengthens; 
the superficial fibrillse, growing more 
than the others, emerge from the spiral 
and form for it a loose fibrillar envelope, 
completely impregnated with a mucoid 
substance. This constitutes the process 
during the course of the development 
of the filament. (Fig. 9, jB.) The 
corneal tissue itself remains normal. 

The filaments are, therefore, formed 
entirely from the epithelium, and are 
similar to the horny excrescences of 
the epidermis. The hyaline cells (iV), 
originally situated within the epithelium, bear some rc^^blance to those 
parasitic organisms known as coccidia, that are ofteqrQ^n in the centre of 
the epithelial nests of epitheliomata. The onlv ^(Wtter is that after the 
parasitic nests have been driven out of the cornp^Tayer the repelling epi¬ 
thelial cells continue to grow and undergo muapre transformation. 

Diagnosis .—Eruptions of filamentafc Keratitis have sometimes been 
confounded with herpes of the cornea.Qnie initial globules and the short 
filaments have been supposed to bq^^sicles, while the long filaments have 
been taken for the shreds of runtJ^STvesicles. 

Treatment .—The removaN^Ohe filaments gives immediate relief, but 
subsequent eruptions oc he intra-epithelial nervous filaments are 

forced into the pedicle. yTJ) e rather violent pains that accompany every new 
eruption are due tP ^[lulling and tugging upon the nerves. The pain 
suddenly ceases onrate removal of the filaments. The employment of a two 
per cent. aqueo^Ssolution of ammonium chloride appears to diminish the 
eruptions h^jvoring the exfoliation of the epithelium. Sattler has recom¬ 
mended shading off the epithelium. In one of the writer’s cases the fila- 
ments^Jirjpnued to be produced from time to time during several years, 
no^itnStanding the employment of various treatments, such as the instil- 
of collyria of methyl-blue, as recommended by Sourdille. 

Epithelial excrescence in filamentary kera¬ 
titis. A, globular form; B , filamentous form 
of the excrescence (free extremity of the fila¬ 
ment) ; T, central spiral portion of the pedicle; 
N, vestiges of hyaline cells "driven out of the 
epithelium. These are in the form of a granu¬ 
lar nucleus surrounded by a capsule of epi¬ 
thelial cells that have more|Or less undergone 
mucoid metamorphosis. 



Similar filaments are expectorated by asthmatics (Curschmann, Nuel). 
Certain cases of bronchial asthma are due to epithelial eruptions of this kind 
in the bronchial tubes. 


Under this title is described (Fuchs, von Reuss, Adler, Groenouw) a 
superficial disease of the cornea, which by reason of its symptoms and 
anatomical lesions (Nuel) constitutes a morbid form that is entirely dis¬ 
tinct from those which have already been described. In the past it has 
been confounded either with catarrhal conjunctivitis, Schwellungskatari'h 
of the German authors, or with a form of superficial keratitis which is not 
well defined. It is usually bilateral, both eyes being attacked simultane¬ 
ously or after many days’ interval. 

Symptoms .—The disease begins with marked ciliary and conjunctival 
injection, slight secretion of mucus, pain, photophobia, and contraction of 
the pupil. This is the catarrhal stage, or stage of invasion. There next 
appear on the cornea small, superficial, yellowish-green spots that are 
fairly well outlined. They number from five or ten to fifty or more, the 
largest having a diameter of one millimetre, but most of them being 
smaller. In searching for them a magnifying glass should be used, other¬ 
wise the real nature of the affection may be overlooked. At the same 
time there is a diffuse oedema, also superficial, which has a smoky appear¬ 
ance, and is sometimes striated. The surface of the cornea is dull, espe¬ 
cially on the level with the larger spots; and it may^so be raised or 
studded with small knob-like projections. The erti^Qms often located 
in the centre of the cornea; at other times it mavfl^ situated nearer the 
periphery, in which case the limbus conjunctivasrtOswollen, and there are 
small elevated spots that resemble phlyctaeni^kQmt which do not ulcerate. 
In the last case there is some secretiomhfiMJiere is neither suppuration 
nor iritis. Some days after the erupti^n\a£ appeared the symptoms sud¬ 
denly cease and the oedema disapg&rs. The corneal spots persist for 
weeks or even months, and go awajQ)[y the process of resorption. 

Etiology .—Superficial punc 
rence between the ages of. 

keratitis is a disease of frequent occur- 
iy and thirty-five years. The greater 
>een exposed to intense cold. It is seen 
has been observed as a complication of 

number of such patient^Hfctfe 
but little except in wi^^, and 
influenza. (j 

Anatomy —The diffuse corneal inflammation is produced chiefly 

by a marked le^ma of the anterior corneal lamellae. The spots are pro¬ 
duced byjyQ$£nts of fibrin undergoing hyaline change, which appear in 
contact^vltli the fixed cells of the cornea. These filaments rolled in spiral 
form ar^situated between the corneal lamellae; they are colored in intense 
rS(^$Wjet by haematoxylin and stain deeply with aniline colors. (Fig. 10.) 

>Tli^e filaments condense in places near the membrane of Bowman, and 
>Si*scmble thick felt. They constitute the spots described above. At the 



level of these areas there is an oedema of the epithelium in the form of 
studs or knob-like epithelial projections that are transformed into epithelial 

In a case of this character which recently came under the writer’s ob¬ 
servation, the nests of spiral filaments were overwhelmed by foci of micro¬ 
cocci that were lodged between the epithelial cells. In Fig. 10 the central 

Fig. 10. 

Longitudinal section of a macula in superficial punctate keratitis. E, epithelium of the cornea; 
B, Bowman’s membrane; N t nerve-canal infiltrated with hyaline filaments arranged in coils. Under 
the macula in the centre of the cut are seen two lacunae in the epithelium, elevating the latter. 

deposits in the epithelium are the seat of the micrococdefiwasion. The 
disease is, therefore, of bacterial origin, and the spiral^y^s are probably 
products of bacteria, analogous to the spiraloid threa^^often of large size, 
which have been described by Loeffler and ottujrafavpresent in growths of 
various other bacteria. 

Superficial punctate keratitis is charact^izfcpgby an inflammatory oedema 
of the anterior corneal planes, due to e^ogf*Ttous (epithelial) infection by a 
not well-identified coccus (staphyloco^j^ according to Valude). At no 
stage is there an infiltration of mig^ory cells. The lesions are located in 
the same places as phlyctaenulae. Qw 

Treatment —All irritan^^(^Hi?ation should be abstained from. At 
the most, lotions of bojic^^m may be employed when there is secretion. 
Atropine may be usedGoJcounteract any contraction of the pupil. Sali¬ 
cylate of sodium in^gLnally has no effect. The exfoliation of the epithe¬ 
lium may demandhOi^Dandage. Dark glasses should be prescribed for the 


ir and Bullous Keratitis .—These pathological forms appear to 
&t <3?ily the epithelium, or at most the superficial lamellae of the cornea, 
are found in eyes having large corneal cicatrices or staphylomata, 



Fig. 11. 

and which are often glaucomatous, blind, and lost in consequence of irido¬ 
cyclitis. Sometimes they appear in eyes which are not otherwise diseased. 
Accompanied by symptoms of rather violent irritation,—ciliary pain, ciliary 
injection, and lacrymation,—there appear suddenly one or more tiny vesicles 
(vesicular keratitis) or very large bullae (bullous keratitis), with clear liquid 
contents, and with a covering which is composed of epithelial cells. In a 
few days’ time the vesicles burst, cicatrization follows, and all symptoms of 
irritation disappear. Some weeks later fresh eruptions take place. Such 
eyes, besides being useless, are a permanent cause of suffering. Often pain¬ 
ful and very rebellious epithelial ulcerations appear, known as the “ re¬ 
lapsing ulcerations” of Arlt, and atheromatous ulcers. The nutrition and 
the sensibility in eyes of this class of cases are profoundly altered. 

The vesicles appear to have a double origin : 1. The lymphatic stasis of 
glaucomatous eyes produces an interstitial oedema of the epithelium, which 
tends to the production of vesicles, etc. (Fuchs). 2. The continual irrita¬ 
tion of the corneal epithelium alters the nutrition of the cells. Above all, 
the cells of the middle layer are transformed into clear vesicles (Fig. 11), 

which in places acquire a very 
large size. The cellular mem¬ 
branes of these large vesicles 
are destroyed, and in this 
manner a lacuna is produced, 
which is often rather large 
and becomes more and more 
distended; <^*h a vesicle is 
covered 1N^epithelium, that 
separatAyt also from Bow- 
matfj^- membrane (Nuel). 
diffuse hyaline and mu- 
alterations of the epi- 
lum also produce those 
epithelial ulcerations which 
are often so painful in eyes 
that are disorganized by glau¬ 
coma or otherwise. 

The first mode of forma¬ 
tion produces vesicle^ccSwcd by epithelium and resting upon Bowman’s 
membrane; the sec^ncHnethod furnishes the intra-epithelial vesicles. Ves¬ 
icles which lie ujvGR substance of the corneal membrane have also been 
described; tlipAa/e said to be developed underneath Bowman’s membrane. 
This poinO<i&^vever, merits further research. 

a o^taption of vesicles is accompanied by pain, which diminishes as 
; recedes. As in filamentary keratitis, the pain seems to be due to 
on of the interepithelial nerve-fibrils. 

fS^Treatment —The removal of the vesicles and of the bullae gives relief. 

A, hyaline degeneration of the corneal epiifaplium, capa¬ 
ble of producing the formation of large eo^J6<ml vesicles 
(bullous keratitis); B, firm excrescences^ 
filamentary keratitis. 


to those of 



Attempts to prevent their recurrence by eradicating the seat of the erup¬ 
tions by cauterization have been unsuccessful. Such procedures will not 
cure either the lymphatic stagnation in glaucomatous eyes or the diffuse 
degeneration of the epithelium. The enucleation of such eyes, the sight of 
which is lost, is often obligatory. Iridectomy performed for the purpose of 
improving the nutrition of the cornea is of doubtful efficacy. Posterior 
sclerotomy is to be preferred to iridectomy. 

Idiopathic Vesicular or Traumatic Vesicular Keratitis .—A vesicular 
keratitis in eyes which are otherwise normal has also been described; it 
occurs spontaneously, most frequently after slight traumatisms. According 
to all appearances, most, if not all, of these forms belong in the class of 
filamentary keratitis. 

Calcareous Keratitis; Ribbon-Shaped Corneal Opacity. —This form of inflammation 
should he compared with bullous keratitis, accompanied as it also is by an alteration of the 
epithelium in disorganized eyes. In eyes that are lost through glaucoma a middle hori¬ 
zontal zone of the cornea is affected; it becomes dull and slightly raised. (See this patho¬ 
logical form discussed under Consequences of Keratitis.) 


These inflammations will be here treated of under the two subheadings 


(a) deep ulcerative and suppurative keratitis and (6) deep non-suppurative 
keratitis. As already stated, those of the first subdivision are caused by 

exhibit the 
efally of con- 


microbic infection, and those of the second 
microbie or non-microbic infection. Cases of the first-' 
characteristics of a local disease; those of the second a 
stitutional origin. 


(a) Ulcers of the Cornea.—An ulcer ^f^^cornea is practically a loss 
of substance which is or has been progreasire^that is, has invaded the sur¬ 
rounding tissues. Some ulcers result frp3Sinjuries to the cornea, and others 
take their origin from cellular inflation which has assumed an ulcerative 
form. In most cases of superfi^imHveratitis ulceration may appear. No 
distinct line of demarcatioii^a^Jpe-arawn between the simple exfoliations 
which heal rapidly and th^-sms^e serious ulcers. Corneal suppurations are 
reserved for a special ^Tiajrfer, although they merge insensibly into non¬ 
suppurative types. The^rincipal features of all ulcers appear to be an 
infection by the rajpj^genic microbes, the yellow and white staphylococci, 
the pneumococofi^clie streptococcus, and, exceptionally, bacilli that have 
not as yet lAA^ell defined. When the microbic infection is pronounced, 
there is suppuration. The greater frequency of corneal as compared with 
conjqm^Mal ulcers is due to the fact that the cornea is not supplied with 
blojjd-Wssels. Thus it follows that the nutrition of this membrane is less 
^HJftesured, and the struggle against microbes is less efficient. 

‘O Vol. iy .—14 



1. Progressive Ulcers. —Extension in depth and width of the ulcer is 
caused by the appearance of new infiltrations. The borders show an opaque, 
yellowish or whitish infiltration, which is sometimes uniform and sometimes 
appears as radiating bands. The intralamellar spaces may be infiltrated 
and hollowed out so as to constitute pockets that are filled with pus. The 
border of the ulcer is encircled by an oedematous areola which spreads 
widely over the cornea or merges insensibly into the surrounding tissue. 
The floor of the ulcer is often irregularly studded with infiltrated areas 
or necrosing corneal lamellae, that are in the process of being cast off by 
the inflammatory process. Sometimes, however, the floor may be trans¬ 
parent and but slightly infiltrated, especially when it is composed of only 
the membrane of Descemet. The depth of the excavation does not gene¬ 
rally correspond with the extent of the destruction of tissue; the lamellae 
of the floor, being swollen, may even project above the surface. Extension 
may sometimes be greatest in depth (boring ulcer). At other times it may 
increase in size (rodent ulcer), and again enlarge in some particular direc¬ 
tion. These are serpiginous ulcers, of which dendritic keratitis is an 
example. Another illustration is the ulcus serpens of Saemisch, for a de¬ 
scription of which see Suppurative Keratitis . Summing up, the floor of 
the ulcer is irregular, spotted, and rarely transparent through its entire 
extent. The borders are almost always infiltrated. Over the floor and at 
the edge the infiltration is intense and of a yellowish-white color whenever 
the suppuration has a tendency to be profuse. The eye is irritated, and 
extreme ciliary injection, lacrymation, photophobia, and ciliary pain are 
present. The iris reacts but slowly to light, and its tisaiAis congested in 
every case in which the ulcer is at all deep. The irft^ may be compli¬ 
cated with posterior synechia or hypopyon. (S ev&typurative Keratitis.) 
The pain and photophobia may be absent even J^vVery grave ulcers, when 
they have assumed a torpid character. 

2. Retrogression of Corneal Ulcers.-^^iph the bactericidal properties 
of the tissue prevail against the de^riWive action of the microbes, the 
ulcer begins to clear up, the shreds of*PwSerosed tissue are thrown off, and the 
epithelium of the sides extends fl$aotfally over the floor or bottom of the 
affected areas, which becomes liffeSpor less bright or polished in appearance. 
The irregular projections d^s^[3@ar during the reparative process. The in¬ 
filtrated area becomes ofWAthifbrm gray tint. Vessels may develop at the 
borders and at the b^Tom^f the larger ulcers. The diffuse oedema of the 
cornea subsides. ThcHsymptoms of reactive inflammation and irritation 
sensibly diminish, ^vhile the loss of substance is being made good. In 
brief, the i^lqp^iears, the grayish floor shines like a mirror, and the lacuna. 

s*yby the loss of the necrosed material is replaced by new tissue. 
^ pain and injection, photophobia, and lacrymation diminish. 

or gap ca\ 
The ciJia^ ] 

tillary contraction disappears, or at least the iris reacts more readily 


^The vascularity of the sides and of the bottoms of ulcers favors the 



nutrition of the tissues, and a‘ds in the limitation of the morbid process. 
Some of'these new vessels proceed from the superficial corneal branches and 
others from the deep vessels. The latter predominate, however, when the 
ulcers are of the deep variety. 

3. Cicatrization of the Ulcer .—The ulcer becomes uniformly covered 
with tissues that are designed to replace those that are already lost. The 
tissue used in the process of repair is at first cellular, and is later trans¬ 
formed into fibrillary cicatricial tissue, which is covered with a layer of 
nearly normal epithelium. Nevertheless, the new connective tissue is 
always distinguishable under the microscope from normal tissue by the 
irregular arrangement of its fibrils. This is the more pronounced where 
the loss of substance has been considerable, especially when the ulcer has 
been deep. The resulting maculae of the cornea are more or less apparent 
according to the extent of the ulcer and the length of time it has remained 
vascular. (See Corneal Maculae.) The vessels gradually disappear, though 
some of them may persist in dense cicatrices. Small ulcers, especially in 
the cornea of children, may disappear without leaving any maculae. Ulcers 
of long duration sometimes do not fill entirely, and thus leave behind a 
corneal depression. This thinned portion is always liable to bulge 
slightly by the pressure exerted upon it, but rarely sufficiently to reach 
the surface of the cornea. The ectatic cicatrix is thus liable to develop into 
a keratec.tasia. 

4. Keratocele .—The membrane of Descemet is distinguished from the 

rest of the corneal tissue by its greater power of resistance Vto injurious 
agencies. When the ulceration has destroyed the corneah ti^ue just in 
front of this membrane, it yields to the intra ocular p^pre and bulges 
forward, remaining transparent and becoming only^j^htly or not at all 
affected. Its free movement upon the overlying jj^r^may cause it to pro¬ 
ject above or in front of a very narrow ulcer, then becomes more or 

less filled by a transparent and mirror-like^^s'fcle. Keratocele usually 
terminates in perforation. The shreds o^^nembrane that are intercalated 
in the ulcer retard the formation of a fi© cicatrix. 

5. Perforation .—An ulcer rnayJ0jforate with or without a preceding 
hernia of the membrane of DesjJ^W- This often takes place in conse¬ 
quence of some effort whichNAiyeases the intra-ocular pressure, such as 
coughing, sneezing, or stooi^f; The patient usually feels a sudden sharp 
pain, which is followed llgyj gush of hot liquid. The aqueous humor runs 
out, the iris and th aortal line lens are brought close to the posterior wall 
of the cornea, thu^pftoTishing the anterior chamber, and the tension of the 
eye is very mqeli^mvered. After perforation the symptoms of keratitis 
generally ah^J^tfhe pains gradually diminish, and the ulcer approaches the 
stage of retn-esfeion. The diminution of the intra-ocular pressure favors the 
intersfcitfRtf^rculation of the nutrient secretions of the cornea. The open- 
ingXcl^ed by the pressure of the iris or the crystalline lens, according 
tqpSHjituation, and it may be further obstructed by the extension of a plug 



of fibrin from the iris. This fibrin becomes infiltrated with young cells, 

and the occlusion is more greatly strengthened by epithelium. Meanwhile 

the aqueous humor reaccumulates, gradually filling the space between the 
cornea in front and the iris and the crystalline lens behind. These organs 

are thus pressed back to their normal positions. Such favorable results fol¬ 

lowing perforation are not the rule, except in the case of small ulcers of 
the cornea. Persistent adhesion of the iris to the corneal cicatrix is termed 
anterior synechia. 

6. Hernia of the Iris .—The iris may become more markedly engaged in 
the opening, being pushed forward by the aqueous humor. Indeed, this 
occurs in the majority of rather large ulcers. A hernia or prolapse of the 
iris is thus produced. The pressure of the aqueous humor tightly holds 
the iris in place, which thickens and forms a grayish-brown prominence on 
the surface of the cornea. A layer of fibrinous exudate ordinarily covers 
the prolapsed iris. As the prolapse of the iris increases, it is held in place 
more and more securely, and is drawn, with the pupil, towards the per¬ 
foration. Rupture may take place by the vesicle giving way; but ere long 
the distention recommences. The tissue of the iris is transformed into a 
red knob that is almost covered with granulations. This reinforcement by 
young, fresh tissue may lead to a sinking in of the prolapse, or to a corneal 
cicatrix with anterior synechia. If the perforation be in or situated near 
the periphery of the cornea, the synechia is drawn towards it, displacing 
the pupil. A central perforation, especially when somewhat large, produces 
a total synechia, involving the entire pupillary marginal The pupil thus 
may be caused to disappear. If the opening be ext^^yei the crystalline 
lens may be expelled at the time of the perforation. ST 

7. Staphyloma .—An extensive prolapse of ris may become cica- 

^gmented posteriorly and 
is produced by the aque- 

trized as a thin fibrillary membrane which 
covered with epithelium anteriorly. An <^( 

An^cmSSs is 


Large cicatrix 

;ornea, with thin walls and with adhesions to the iris. To the right and 

left are stumps offorjeal tissue that are thickened by oedema : C, corneal cicatrix, formed principally 
by the iris, a*idu>iHmented on its under surface; «S, canal of Schlemm; C.C. ciliary body; I, iris; A. 
CH. anteri^- clS^Bber; B, semicylindrical prominence formed by the iris. 

ous hkmor pushing the cicatrix forward. (Fig. 12.) More of the cornea 
g^Vway under the pressure, and a staphyloma, which consists of the 
Xrofapsed iris, cicatrized on its surface and covered over with epithelium, is 
f^produced. The staphyloma may also result from a very narrow perfora- 



tion in which its borders are considerably thinned. They are unable to re¬ 
sist the intra-ocular pressure and are pushed forward with the iris, which 
firmly adheres to them. In this case the covering of the staphyloma is 
mainly composed of corneal tissue. This contingency is greatly to be feared 
when there is a large anterior synechia, and especially when there is a total 
synechia of the pupillary border. The aqueous humor being no longer able 
to flow into the irido-corneal angle, the eye becomes hard and glaucomatous. 
This contributes to the bulging of the cicatrix. A stapliylomatous eye is 
either glaucomatous from the first or soon becomes so. 

. 8. Glaucoma .—A cicatrix with an anterior synechia may be so firmly 
fixed as not to become ectatic. If, however, the synechia is large, and 
particularly if there be total synechia of the pupil, the eye will be ulti¬ 
mately lost from glaucoma. Finally, the traction on the iris and the deep 
infection of the eye may lead to an iridocyclitis, a phthisis, or a panoph¬ 
thalmitis, or to intra-ocular hemorrhage that may disorganize the eyeball. 

9. Fistula of the Cornea .—An opening made at the time of perforation 
may remain patulous for days or even weeks. In such a case a true cor¬ 
neal fistula has not been produced, but a fistulous staphyloma, which will 
be considered later in connection with a description of the other varieties 
of staphylomata. 

Etiology .—The chief predisposing cause of corneal ulcers is the absence 
of blood vessels in the cornea, which are so efficient in the struggle against 
the microbes. The contrary holds good in small erosions and infiltrations 
of the conjunctiva, that generally heal quickly because of inch vascular 
supply. The more direct causes of ulcers are of two classq^A traumatic; 

2, microbic. (See Superficial Traumatic Keratitis .) Usi 

oth of these 

causes are required to produce an ulcer, especially >sfivwhich lasts any 
period of time. As has already been stated, the AfcMom of infection by 
pathogenic organisms enables the ulcer, which tfcSwreally does not deserve 
this name, to heal rapidly. 

1. Traumatic Causes .—(a) It is not ^ece^ary to mention here all the 
ways in which injuries may give rise to erficial keratitis. (See Superfi¬ 
cial Traumatic Keratitis.) Traumattejns that persist or are often repeated 
generally result in the formation ((njulcers. An important cause favoring 
the repetition is the non-occl^teji^or the eye, either in consequence of in¬ 
sufficiency of the lids, coiigei^tjVor cicatricial, or because of the insensibility 
of the eye from partial ct general trigeminal paralysis. Winking need not 
be abolished, as it mi^std! occur through the influence of the sensibility 
of the other eye. Jt&vtfcles of dust striking an eye without sensibility no 
longer pro vol^e ^Cfc^reflex winking and lacrymation that are necessary to 
eject them.^^Ntlnking is diminished or suppressed, the inflammation 
may assume mb character of a neuroparalytic keratitis. Grave affections 
that lDw^Vhe general sensibility, such as enteric fever or typhoid states, 
hav^usmlly the same effect. The same is true of variola, in which con- 
he corneal erosions are in addition infected. 



( b ) Among traumatic causes conjunctival and palpebral lesions, such 
as granulations and cicatrices of the conjunctiva and of the ciliary border, 
absence or deviation of the cilia, and irregularities of the conjunctiva of 
the upper lids, are all of especial importance. Conjunctival catarrh rarely 
produces ulcers of the cornea, except in aged people. They occur most fre¬ 
quently under the form of peripheral growths that commence as infiltra¬ 
tions. Blennorrhoea acts in two ways,—by the friction of the turgid, puffed 
conjunctiva against the cornea, producing superficial exfoliation, and by 
compressing the nutrient vessels of the cornea. The pus is, moreover, a 
cause of infection. This is likewise the case with diphtheritic conjunc¬ 
tivitis, in which the diphtheritic and other microbes infect the traumatic 
superficial exfoliations. 

(c) All the lesions that produce superficial keratitis, such as corneal 
phlyctenules, conjunctival herpes, vesicular keratitis, etc., may become the 
starting-points of very serious ulcers. In many of these cases of superficial 
keratitis small ulcers form, which, though infected, have not the tendency 
to progress. To bring this about, a special cause of infection seems to be 
necessary. Maladies usually described as superficial may have already 
become of serious import by the development of ulcers, such as are seen in 
dendritic keratitis, rodent ulcer, and herpes zoster of the cornea. 

2. Causes of Infection .—The cornea may become infected from blennor¬ 
rhoea, diphtheria, or secreting granulations of the conjunctiva. Ulcerous 
and non-ulcerous blepharitis and blennorrhoea of the lacrymal sac are fre¬ 
quent sources of infection, as well as eruptions of the face,*eczema, pimples, 
coryza, and, above all, ozsena. Infectious germs miw^Vthe hands or a 
handkerchief be conveyed to the eye from eruptiow^NJliruncles, wounds, 
etc., situated on any part of the body, and espegiflCyTrom those affecting 
the nose. Many of the agencies causing the toipnatism, such as particles 
of earth, stone, blades of straw, hay, etc., isSfoeT the cornea while wound¬ 
ing it. (See also Suppurative Keratitis 

Prognosis. —As to the effect on &skM\ the prognosis in cases of ulcer 
is very variable, and can be mac^rnly by a judicious estimate of the 
numerous factors which have j^n previously^ specified. The influences 
that contribute to produce th^^esult are the locality, the depth and size, 
and the degree of infecti^V^ tne ulcer. A peripheral ulcer of small size 
produces a macula whitrfTynly slightly interferes with vision. On the other 
hand, sight is dimir^shicTor even abolished if the macula encroaches on the 
pupil. (See arji^s on Corneal Macula and Corneal Staphylomata .) 

Treatment. /•^Kfiere are few diseases in which appropriate and judicious 
treatment* o^fc^Tses so favorable an influence as in ulcers of the cornea. 
Excitii^^^Nses of injury should be diligently searched for and eliminated 
as fai\asSpossible. Cilia which rub against the cornea and also papilloma- 
t^sy^crescences of the conjunctiva should be removed. Sojourn in a 
idirsty atmosphere or in the rain, etc., should be interdicted. Foci of infec- 
►>fon, such as blepharitis or blennorrhoea of the lacrymal sac are to be de- 



stroyed, or at least abated,—the blepharitis by antiseptic measures, and the 
diseases of the lacrymal passages by sounds and boric acid injections. Any 
eruption of the skin on the face or elsewhere and all nasal affections should 
receive appropriate treatment. Catarrh of the conjunctiva, whether it has 
preceded or has been caused by the ulcer, should be treated, with careful 
avoidance of remedies that might irritate the diseased cornea. Boric acid 
lotions should be used frequently. The palpebral conjunctiva may be cau¬ 
tiously touched with nitrate of silver, the cornea being well protected and 
the effect of the caustic neutralized with chloride of sodium. The indi¬ 
cations for treatment in ordinary cases may be summed up to be, the use 
of antiseptic lotions, instillations of atropine, and the use of a bandage. 
The occlusive and compressive bandages play leading roles in the treatment 
of corneal ulcers. They immobilize the lids and prevent them from irri¬ 
tating the ulcers, and thus often allay superficial pain. They protect the 
ulcer from dust-particles, which winking would not be able to remove from 
the excavations. They prevent the free border of the lids, this receptacle 
for microbes, from infecting the ulcer. When compressed a little more 
firmly they support the base of a deep ulcer, preventing it from yielding 
and perforating. (See General Pathology .) 

A profuse secretion, as in cases of blennorrhcea, diphtheria, or granula¬ 
tions, may be a contraindication to the employment of the bandage. The 
reason for this is that the retained secretions undergo decomposition, and 
thus infect the ulcer. 

Atropine .—The employment of atropine can seldom be dispensed with. 
The indication for its use is given by the signs of congestioAof the iris,— 
ciliary pain, contraction, and sluggishness of the iris thlj^ ^Dilatation of 
the pupil immediately alleviates ciliary pain and cauaG^wmprovement in the 
appearance of the ulcer. Furthermore, the drug^A^nts the formation of 
posterior synechia and breaks recent adhesion&^After the healing of the 
ulcer the synechia may impair vision and ursmd b glaucoma. The contrain¬ 
dications resulting from the presence of^la^e/anterior or posterior synechiee 
must not be forgotten. Every time tpNatropine fails to dilate the pupil it 
tends to render the eye glaucomatoys. and in such a case should not be em¬ 
ployed. In such a case the wrifcuMrould prefer instillations of eserine or, 
rather, of pilocarpine, whichJ^Rf^F ainful, three or four times a day. Some 
authors recommend mioticw^all cases of corneal ulcer. This is done for 
the purpose of dimini|!7irig4he pressure in the anterior chamber, especially 
when there is danger ^perforation. Instillations of miotics are disliked 
because they all f^fScially eserine) produce ciliary pain and favor the for¬ 
mation of syna^fctf by maintaining the iris closely against the crystalline 

lens - . o&y 

Antisqtys .—Corrosive sublimate solution or a solution of cyanide of 
mercurj^should be liberally used one or more times daily in cleansing the 
CQ^rr^tival sac and the ciliary margins of the lids. Lotions of this kind, 
cabined with atropine and followed by a bandage, suffice in most cases. 



A greater degree of infection, indicated by marked infiltration, violent 
reaction, extreme congestion of the iris, and rapid progress of the ulcer, 
however, demands the employment of more energetic and more lasting 
antiseptics. Iodoform insufflated under the lids, followed by a bandage 
over the eye, has an action that is less intense, but more lasting. The con¬ 
junctival secretion is also slightly diminished by its use. Applications of 
the crayon of pyoktanine (preferably the methyl blue) over the bottom and 
the infiltrated margin may produce very marked amelioration in the ap¬ 
pearance of the ulcer.—In cases of intense infection and rapid progress, 
cauterization by heat (see vol. iii. p. 823) is the sovereign remedy, and is 
usually very efficacious. The floor and especially the infiltrated borders of 
a reddening ulcer, which is progressing rapidly, must be cauterized. Per¬ 
foration of the cornea should be avoided, although the mischief caused 
thereby will be minimized through a chilling of the cautery by the aqueous 
humor. A distinct cicatricial macula will remain upon the healing of such 
an opening.—Instillations of cocaine should precede all applications of the 
cautery or of the crayon of pyoktanine to the cornea; it may even be ad¬ 
visable to instil it before making a simple examination of the eye or apply¬ 
ing a lotion. It has no beneficial influence on the ulcer itself. 

Paracentesis .—If spontaneous perforation (the happy effects of which 
have already been described) seems likely to occur, it is better that the 
opening should be made by the surgeon, preferably in a healthy portion of 
the periphery of the cornea. Hernia of the iris and other grave accidents 
are more easily avoided when paracentesis is done in normal corneal tissue. 
Absolute rest of the patient should be enjoined whenevfc^perforation is 

If there be perforation without notable attachm#M>fr the iris, ordinary 
treatment is sufficient. A true prolapse of the ip&nould be released after 
cocainization either by excision or by the act^^i?autery. When the pro¬ 
lapsed iris slips away in front of the scis.^P^S^s necessary to pierce and in¬ 
cise it laterally by means of a von Grqgfi^er a Beer knife, and then to ex¬ 
cise it with a scissors. Excision an*Wkuterization are, however, of little 
use if the prolapse be very large, i^it it may be made smaller by repeated 
punctures.—An iridectomy whiarfSS^establishes access of the aqueous humor 
in the anterior chamber is ocMwe best means of flattening a prolapse and 
of obtaining a firm, resistH^Vicatrix.—In a central prolapse of moderate 
size, atropine acts fav^raBly by drawing the iris towards the periphery; if 
the prolapse be a larger one, this drug is not only useless, but tends to 
augment it. Th<Vf«fter cases call for the use of eserine, which acts very 
favorably in dAipheral prolapses that are not exceedingly large. The 
action of ^A$rug is to flatten them sensibly by augmenting the resistance 
of the irisS^In those synechise in which there is a wedging in or an enclosing 
of it has been recommended (A. Meyer, etc.) to cover the perforation 

(^teSdme edges have been curetted) with a fragment of conjunctiva that has 
iously been detached and drawn over the opening by means of a suture. 



This operation is especially useful if the iris reaches the surface, thereby 
exposing it later on to infection. The conjunctiva adheres to the ulcer and 
reinforces the cicatrix.—A keratocele should be pierced or tapped. (Con¬ 
cerning the sequelae of ulcers, see Maculae and Staphylomata of the Cornea.') 

Irritant remedies may be cautiously tried, if the period of progression 
tends to be prolonged and if there are corneal facets. The mildest of these 
consist in the application of hot compresses. Calomel is more energetic; 
and still more so is the yellow oxide of mercury ointment, employed as in 
phlyctenular disease. When an ulcer has lasted for a long while and has 
become indolent, scraping of its bottom and sides with a small metallic 
spatula is often attended with most beneficial results. 

(6) Suppurative Keratitis ; Suppurative Ulcer and Abscess of the 
Cornea. —The gravity of the situation is augmented in keratitis by copious 
suppuration, which tends largely to destroy the cornea, and to produce per¬ 
foration, staphyloma, etc. 

1. Ulcer and Abscess .—Suppuration may follow a traumatic loss of cor¬ 
neal substance and render a simple ulcer purulent. A keratitis may be 
openly or freely suppurative at first, but more frequently suppuration com¬ 
mences later by a dense, cellular infiltration of the tissue of the cornea, which 
it softens and destroys. Before the central softening is completed the infil¬ 
tration ulcerates through the surface, exposing the infiltrated and partly 
necrosed corneal tissue. It never forms an abscess in the usual signification 
of the word,—a cavity filled with pus, discharging its contents later through 
a narrow opening,—even when the infiltration has been primarily deep. 
Some authors use the word abscess when the sides or borc^K^^ an ulcera¬ 
tion are undermined or are hollowed out, constituting sigmas for the pus. 
The border is then more opaque than the centre. Otl^vauthorities apply 
the term abscess to ulcers which have a very irreguh^mse or floor on which 
shreds of necrossed tissue remain for some timeJ^Sre being eliminated. 

2. Symptoms .—A purulent infiltration if5o§|^ing no opening for the 

escape of the accumulated pus may vary nsr^iegree of intensity and size. 
It is important to be able to recognize bscess which has a tendency to 
produce wide and deep destruction ofi^issue. If it be small and superficial, 
there appears a small prominence oQ&e corneal surface; if it be deep-seated, 
the cornea may only assume of dulness without any elevation of 

its surface. In every case it iyuistinguished by an intense yellowish-white 
color (not grayish or tra^jijcent), which diminishes towards the periphery 
and merges into a slig^h' congested cedematous zone, and may be gradually 
lost in the unaffcctod^trtions of the cornea. 

A deep pu^i^fe^b-nnfiltration usually increases in size before it ulcerates. 
The color i^ti^ihtense yellowish white; where the tint is less intense and 
grayish, th£ irantrations do not tend to suppuration or softening. The oedem- 
atous ordinarily extends over the entire cornea, which appears dull 

thrcJ^lNrts entire extent. The symptoms are violent; there are extreme 
crwR^and conjunctival injection and iritis, and sooner or later hypopyon 



supervenes. Pain may, however, be absent. Quite often there is tactile 
anaesthesia of the cornea. 

The floor of a suppurative ulcer is generally very irregular, and in some 
places it is infiltrated; the borders may also be infiltrated and constitute 
pockets in which the pus stagnates. It is useless to subdivide suppurative 
ulcers any further, though the ulcus serpens (Saemisch) or serpiginous ulcer 
merits special mention. It is rather large, is situated in the central por¬ 
tion of the cornea, and develops only through infiltration of one side. In 
addition, the epithelium may even advance over or towards the ulcer, which 
becomes elliptical. There is hypopyon, with a tendency to colliquation of 
the cornea. 

According to Uhthoff and Axenfeld, the pneumococcus is the exciting 
agent in nearly all cases of serpiginous ulcers of Saemisch. This organism 
is normally present in the nose, the throat, and the lacrymal ducts, and 
takes an active part in inflammatory lesions of these regions. It is, there¬ 
fore, easy to understand how it gains access to the eye with the greatest 

3. Hypopyon .—Certain authors speak of a suppurative keratitis only 
when there is hypopyon,—that is, when there is pus in the anterior cham¬ 
ber. The pus on mingling with the aqueous humor sinks to the bottom of 
the anterior chamber, where it forms a yellowish-white collection, which is 
horizontal or even slightly concave on top. Most frequently the composi¬ 
tion of the pus is compact and fibrinous; rarely it is liquid, and then it 
is displaced when the head is inclined in different positions. Where the 
hypopyon is small, it is called an “ onyx,” because of iteN^semblance to the 
root of the nail. The amount may be so insignificwOthat it is concealed 
behind the limbus conjunctive, and can be discp^^efl only by examining 
the eye obliquely from above downward. Tl^Aj^ may reach the level of 
the pupil or even fill the anterior chamber.'OjJypopyon is an exceedingly 
grave complication in a case of kera^itSsS J Although a small hypopyon 
may disappear by resorption, a large bto&f invading the major part of the 
anterior chamber, tends to productrj^bcrosis of the cornea and destruction 

The pus of hypopyon issues from the irido-corneal angle, from the iris, 

of sight in the affected eye. 

and, in severe cases, also^r^^wie ciliary body, from whence it flows across 
the pupil. It was for^alvhg time supposed that hypopyon was a corneal 
abscess which had (^enNi posteriorly, or that the pus-cells passed through 
the interstices of J^li^posterior corneal lamellae (Horner). It is true that 
yellowish puSit>^S?s on the posterior face of the cornea may be seen ex¬ 
tending do^SJrd from the level of the ulcer to the hypopyon. These 
are con^A^S of filaments of fibrin, impregnated with cells, which are de¬ 
posited preference behind the ulcer, in which situation the endothelium 
d and may even be elevated or lifted off (Leber). Experimental in- 
n*of the cornea with pyogenic organisms made upon animals shows 
at in hypopyon the posterior planes of the cornea may be intact and even 




Fig. 13. 

remain free from cellular infiltration. Fig. 13 is a cross-section of an eye 
affected by a serpiginous ulcer (of Saemisch) of moderate severity, which 
would probably have healed if 
the patient had not died of an 
intercurrent pneumonia. The 
deep corneal planes are intact 
and without cellular infiltra¬ 
tion. The fibrinous hypopyon 
extends to the inferior border 
of the dilated pupil. It is in¬ 
filtrated by cells, especially in 
its anterior planes. Its pos¬ 
terior portion is composed 
of filaments of fibrin, that 
were probably furnished by 
the iris. The cellular de¬ 
posits seem to issue from the 
irido-corneal angle, or per¬ 
haps from the pupillary mar¬ 
gin of the iris. A thin layer 
of pus exists in the posterior 
chamber, which is most con¬ 
spicuous in its lower portions; 
it extends throughout the cil¬ 
iary body as far as the ora 
serrata, where it penetrates 
the vitreous humor, as shown 
by the small abscess at (A) 
in the illustration, and by a 
little accumulation of pus (P) situated bflTte^the crystalline lens. The 
iris and the ciliary processes are infiltratocNby a homogeneous exudate and 
their vessels are markedly congested.£\rhe periphery of the iris is more 
or less adherent to the cornea. rp 

Hypopyon, therefore, may tf*ansform a simple inflammation of the 
cornea into a keratitis comjAk0^crwith grave iritis, or even into a cyclitis, 
—that is, into a disease oHfviib whole anterior segment of the eye. This 
explains the long dura^orjSi the malady and the persistent irritation, even 
when the ulcer presets an improved appearance. Still it is to be supposed 

Corneal ulcer with hypopyon (ulcus serpens); occurring 
in a case of fatal pneumonia (Nuel). I and E, limits of the 
corneal ulcer; I, area of infiltration at the edge of the ulcer 
rendering it progressive; H, hypopy^nV its lower portion 
consists of a deposit of pus, whicli^l^p^meates the whole 
of the ciliary body; P, deposit ojlrra^elns behind the crys¬ 
talline lens; A, small abscess oftl^^itreous body, the pus of 
which has extended from serrata; Z, ora serrata; 

F, free parenchyma and hjterae of the vitreous body; R, 
anterior limit of the retifc^roper. 

that in cases of 
the iris to th£ 

Si mil; 

feld, ancl^ o 

hypopyon the suppuration does not extend behind 
degree as it does in severe ones, 
have since been described anatomically by Uhthoff, Axen- 
£rs. According to Elschnig, a perforation of the membrane 

et has been found by Verdese, Green, and Ewing in cases where 
^omeal tissue proper was not yet perforated. This point needs further 
inwltigation. It is sujiposed that the migratory cells which have accumu- 



lated in front of Descemet’s membrane corrode its tissue by histolysis, just 
as they do in detaching the necrosed parts of the fundus of an ulcer. 

There are no microbes in an hypopyon like that shown in Fig. 13, 
the deposit of pus within the eye being induced by the irritating action 
of the bacteria found on the cornea. We admit that phlogogenic sub¬ 
stances secreted by the intracorneal microbes (in cases of non-perforation) 
diffuse themselves in the pericorneal vessels, where they provoke dilatation 
of the pericorneal vessels and emigration of migratory cells. In the same 
manner the phlogogenic substances are diffused in the anterior chamber 
and the iris, and, if they reach this membrane in sufficient quantity, they 
give rise to iritis and hypopyon, the latter being an exudation from the 
iridian vessels. When bacteria are present in an hypopyon, the affection 
has a tendency to develop into panophthalmitis. This is likely to happen 
after perforation of the cornea. 

The purulent secretion on the surface of the diseased eye comes partly 
from the cornea and partly from the conjunctiva after the latter has become 

Suppurative keratitis on healing will leave a dense macula even when 
it is arrested before perforation occurs. After perforation has taken place, 
all the consequences resulting from ulcers may be observed. Staphyloma is 
most to be feared. 

Anterior polar cataracts,—distinct from pyramidal cataracts,—consisting of small, 
well-defined, circular, nacreous, white spots, not projecting into the anterior chamber, and 
which are usually considered to be of congenital formation, are generally formed in extra- 
uterine life, and usually follow ophthalmia neonatorum complicat^^ath ulcus cornese, 
with or without perforation of the membrane.—The phlogogeni TO •stances above men¬ 
tioned, secreted by the intracorneal microbes, diffuse themselvei^j|i cases of non-perfora¬ 
tion) in the aqueous humor and set up iritis. At the pupil^A^come in contact with the 
lens capsule, which is here not protected by the iris, m/TVVnetrate to the capsular epi¬ 
thelium. The epithelial cells, which are still in full3^mitive activity at this age, are 
irritated and proliferate, forming the laminated constitutes the cataract. At a 

more advanced period of life non-perforating cor^al^ilcers (unaccompanied by hypopyon) 
never give rise to the same disturbance of thaUens, partly because the capsular cells are 
relatively inactive and partly because the ar^^OT chamber is deeper. (Nuel.) 

ratitis is always the result of severe mi- 

dr. Etiology .—Suppurat i ve 
crobic infection, which is < eWgjoHe to the presence of a larger number of 
microbes than in a non-puripent ulcer or because the bacteria themselves 
have assumed a grea^r rmilence. At times the resistance of the corneal 
tissues seems to bejimmiished, owing to the existence of a grave general 
malady or a copA^Son of the cornea. The infection always comes from 
without, thr()j<iA/a loss of substance, which may be sometimes insignifi¬ 
cant, of tl^Stfh’face of the cornea. The writer regards as erroneous the 
belief thab^hdogenous (metastatic) infection may occur in suppurative kera- 
titis^^pervening in infectious diseases, such as variola, typhus, scarlatina, 
ajjd ail maladies of a typhoid character, like pneumonia. 

^OThere must always be a cause of injury and a source of infection. As 



to causes of injury, it is only necessary to recall what has already been said 
of ulcers in general. In wounds or contusion of the cornea, the microbes 
in the conjunctival sac appear to be sufficient to provoke suppuration. The 
body wounding the cornea may be infected at the time of injury. Bits of 
earth or stone, the beard of wheat, and fragments of straw seem to be capa¬ 
ble of producing infection, as shown in the keratitis of reapers. Three- 
fourths of ulcers with hypopyon have their source of infection in diseases 
of the lacrymal passages, which should, therefore, always be examined in 
cases of this kind. Even in cases of simple obstruction of the lacrymal 
ducts, the secretion, which is held in the lacrymal sac until it flows back 
into the conjunctival sac, contains the bacteria of suppuration, such as the 
staphylococcus, the pneumococcus, and, at times, the streptococcus. It is 
the same with the nasal secretions, in cases of rhinological ailments, es¬ 
pecially in ozaena. The conveying of the secretion (through the fingers, 
the handkerchief, etc.) to the eye is quite easy of accomplishment. It 
would seem also that, in the case of diseases of the throat, the secretion of 
this part of the body may infect the eye in like manner. A frequent cause 
of serious corneal infection is to be found in furuncles and in all eruptions 
that are situated near the eye. Conjunctival maladies, diphtheria, blennor- 
rhoea, and secreting granulations may also be cited as causes of suppurating 

corneal ulcers. 

In about two per cent, of the cases of variola, abscess of the cornea 
supervenes most frequently during the period of desquamation. The erup¬ 
tion of pustules upon the cornea in such a case must not baconsidered as 
having the same origin as that upon the skin. A pari^it^jiffected with 
small-pox, for example, is unable to close the lids, tfTJH^rhe open eye is 
bathed with pus and fragments of crusts. 

Exceptionally, a variolous papule may develop on^^^onjunctival limbus. Con¬ 
junctival diphtheria, which so often covers the wjj^h^^rneal surface with pus, extends 
only exceptionally to the cornea. Formerly the irtolwiSent of the cornea was considered 
to he caused by necrosis due to lack of nourishi^ntr"^t present the opinion is expressed 
that it results from pyogenic microbes penetr*TV^ through the small corne d sores, which 
must of necessity occur in conjunctival dinhthem. According to H. Coppez, the entrance 
of bacterial toxines into the corneal tissue tjfflild also be taken into consideration as a factor 
in the production of this condition. though gonococci have been found in the cor¬ 

neal lamellae of suppurative ke^te§^$blfowing gonorrhoeal conjunctivitis, it would seem 
that this, also, is a case of infiwol^ of the cornea (through small ulcers) by pyogenic 
microbes. The progress of/fJTeJiiphtherial and gonorrhoeal infection appears to be favored 
by compression of the supernal ciliary vessels. 

In isolated (^s^uilcerous and purulent keratitis has been caused by 
mycelia from ijffhgT that have invaded the tissue proper of the cornea (Leber, 
Schirmer fliers). 

5. Prognosis .—The prognosis in suppurative keratitis is always serious. 
Firs^oJr^l, any part of the cornea that is invaded by the purulent process 
isXuiVio be, under the most favorable circumstances, opaque after cica- 
ion. Frequently, after the disease is cured, posterior synechia will 



remain ; and if they be numerous, they destroy the sight and predispose the 
eye to glaucoma. The latter condition may necessitate an iridectomy. It 
is not rare to find, later on, that the crystalline lens has grown opaque 
(cataract). The greatest danger that threatens such eyes is the presence of 
corneal staphyloma, the tendency of which is to destroy the sight. (See 
Corneal Staphyloma.) In the case of perforation a staphyloma is greatly to 
be feared, on account of the softening and the destruction of the corneal 
tissue. The greatest number of staphylomas result from suppurative kera¬ 
titis. Sometimes the infection invades the depths of the eye and leads to 

6. Treatment .—The treatment is the same as that of grave corneal ulcers. 
In mild cases ordinary measures may suffice (see Corneal Ulcere), but ex¬ 
tensive suppuration calls for the employment of the most energetic bacteri¬ 
cidal remedies with cauterization by heat (see vol. iii. p. 823). Experience 
has proved that when an hypopyon has reached the inferior border of the 
pupil, resorption of the pus is no longer possible. It must then be evacu¬ 
ated by paracentesis. This can sometimes best be accomplished by the use 
of forceps or by injection of the physiological solution of salt. If possible, 
the puncture should be made below the level of the pus into a portion of 
the cornea which is still healthy. In large ulcers which are threatening to 
perforate and in grave ulcus serpens the original incision recommended by 
Saemiseh (see vol. iii. p. 827) may be made. This method has been less 
often resorted to since the introduction of antiseptic measures, and, above 
all, of cauterization by heat. The anterior chamber is opened with a von 
Graefe knife through a portion of the unaffected corne^elfy the ulcer, and 
a counterpuncture is made in the healthy cornea oirtuVe opposite side of 
the ulcer. The two openings are then connected J^Vn incision extending 
through the greater diameter of the cornea. I®? iressure on the posterior 
side of the cornea is diminished, and the ou^^ing aqueous humor carries 
away the pus. The borders have a tenien^^o become agglutinated, and 
should be daily reopened. If the cas^dmT^resses favorably, the result will 
be a cicatrix with a large anterior sy^^nia. 

In a large hypopyon the em^vment of atropine is without beneficial 
effects. Its use augments the(o)mger of perforation, and the paralysis of 
the iris and the synechise ^VMhHlie pupil from dilating. 

Lavage of the anterjfTij^ehamber with antiseptics has not given good 
results. Corrosive sublimate solutions, particularly, are exceedingly irri¬ 
tating, and all of the other salts of mercury per se give rise to a persistent 
opacity of the cornea. 

During* t^T^last few years, subconjunctival injections of the bichloride 
of merci^N^^e been tried (Darier, Abadie, de Wecker, and others). After 
cocainizanWn, several drops or even larger amounts (de Wecker) of the 
coirasf^ sublimate solution of the strength of 1 to 2000 or 1 to 1000 are 
foyectea beneath the conjunctiva. For the same purpose Chibret recom- 
^a«mds the cyanide of mercury, as less irritating than the corrosive subli- 



mate. He uses half a syringeful of an aqueous solution of the cyanide of 
mercury in the strength of 1 to 200, or even 1 to 100. Though this treat¬ 
ment appears to be founded on rational principles, especially as Pfliiger 
has shown that substances thus injected beneath the conjunctiva really 
reach the cornea, it does not seem to have given better results than when 
the antiseptics are applied by other methods. Indeed, Bachleur, from his 
experiments on rabbits, disputes their efficacy. In addition, the injections 
are attended with considerable pain, as the cocaine is not capable of render¬ 
ing an inflamed eye insensible. One can thus understand how the first 
enthusiasm for this mode of treatment has disappeared, and how the ten¬ 
dency at the present time is to abandon its employment. 

Injection (beneath the conjunctiva) or instillation of anti-staphylococcus 
or anti-streptococcus serum has not yet been of real benefit. 

A priori , the use of wet corrosive sublimate compresses would appear 
to be of use in bringing the cornea in continuous contact with this anti¬ 
septic. Though often employed, they do not seem to produce markedly 
favorable results. This is due, in the writer’s opinion, to the secretion from 
the conjunctival sac not being absorbed by the material employed for the 
compress when it is in a moist state. 

The rule is to use dry compresses, which are to be renewed two or three 
times each day, at which time the eye is to be thoroughly cleansed with the 
solution of corrosive sublimate or of cyanide of mercury. When iodoform 
has been sprinkled on the compress, lavage with the bichloride of mercury 
solution must not be practised; the solution of the cyanide of mercury or 
of boracic acid can, however, be employed along with the iocloArm. 

Atropine is often used, care being taken to watch cara^lly its action 
upon the pupil: if it dilates, its effect is relatively bercfefial. If it does 
not do so, as in the case of a large hypopyon, the acjjj^of the mydriatic is 
injurious. (See Treatment of Corneal Ulcers .) se cases the use of 

miotics is often painful and unattended with a^Qesults. 

Warm compresses, applied for an hourVfc^ time once or twice a day, 
often do good, as they favor the interstitLaJSiutrition of the cornea. 

Ill every case care must be takej^tcMnsure cleanliness of the eye by 
daily repeated lotions of the conjun-atjCAl pocket with mild antiseptic solu¬ 
tions of sublimate, boric acid, ^tq^^W cases of great conjunctival secretion 
the application of iodoform m^j^oe useful. 

(c) Keratitis with ox/from Lagophthalmos; Neuroparalytic Kera¬ 
titis.—The forms of krMs designated by these names have the charac¬ 
teristic in common oMSig primarily dependent upon injuries of the cornea 
due to the defectWAaction of the lids. Secondary invasion by pathogenic 
organisms natAAQy cailse these lesions to assume a more serious type. They 
are in the maltreated of in the preceding pages; some in connection with 
corneaLutes^s, the others with suppurative keratitis. Neuroparalytic kera¬ 
titis ig imnally described separately, partly because of its clinical features 
tly because of its supposed etiology and pathogenesis. Keratitis 


is js IP 



with lagophthalmos is considered here because it is mainly due to the same 
cause as neuroparalytic keratitis, and in time becomes converted into this 
type of keratitis. 

Keratitis with Lagophthalmos .—The causes are the same as those enu¬ 
merated in the preceding pages ; everything which obstructs or prevents the 
normal occlusion of the lids, ectropion, insufficiency or shortening of the 
lids, either congenital or acquired, from cicatrices, exophthalmos, retrobulbar 
tumors, Graves’s disease, etc. 

Paralysis of the facial nerve acts in the same way. When thus ex¬ 
posed, the normal cornea, especially its lower segment, desiccates and ex¬ 
foliates, and the conjunctiva becomes irritated. During sleep, the reflex¬ 
winking being suppressed, the eye remains more or less open. During 
the day the affected eye hides itself under the upper lid, which does not 
wholly perform its normal function of removing the foreign particles that 
collect upon the cornea. Traumatic ulcers that may become infected, 
and which are situated most frequently in the inferior half of the cornea, 
may result. 

Keratitis associated with a typhoid state has an analogous origin, though 
it more nearly approaches the neuroparalytic form. 

Treatment .—The main points to be attended to are: (a) the protection 
of the eye with a bandage, which may have to be worn even at night; and 
(6) the use of antiseptics. Cicatrices in the region of the eye sometimes 
call for operative measures. 

Neuroparalytic Keratitis .—Trigeminal disturbance, which is always 
more or less anaesthetic in type, may be accompanied k>4erpes zoster of 
the cornea. Though this condition has probably a special pathogenesis,— 
a neuritis extending to the cornea,—it will be consp^Ped in this connection, 
owing to its close relation with the matter now/ryder discussion. 

True neuroparalytic keratitis is observ^KtfT complete paralysis of the 
trigeminus or in one of its ocular branc|(fS?Ya^a especially the nasal branch. 
Under these conditions the reflex a^tioh-*of winking and of lacrymation 
does not take place. The eye orclinrfTwy remains open, its surface becoming 
dry in the same manner as if it^aobeen cocainized. The eyeball—espe¬ 
cially the cornea—is no longtfNriTotected by that guardian of the eye, the 
trigeminus, and is expo^ Diffusions, foreign bodies, and desiccation 

by evaporation of whaMvtle moisture there may be there, the secretion 
of tears having been alraidy suppressed. Thus the conjunctiva becomes 
irritated, and th^*comea exfoliates more and more. Sooner or later the 
wound become§>^?ected and the infiltration extends in depth. Usually 
the centre aMW cornea is especially involved, the extreme periphery of 
the corn^S^naining relatively undisturbed. Suppuration now takes place 
and an n^popyon is produced. The picture of a typical case is completed 
witj^Krforation, loss of tissue, staphyloma, and phthisis bulbi. In favor- 
>abr^cases cure is effected with a large central leucoma, which later on may 
^rmit of the performance of an iridectomy. 



The the.ory of neuroparalytic keratitis dates from Magendie, who saw 
suppurative keratitis supervene in rabbits in which he had divided the tri¬ 
geminal nerve within the cranium. It is supposed that there are in the 
trigeminus trophic nerve-fibres which preside directly over the nutrition of 
the elements of the cornea, very much as the motor nerves act on the mus¬ 
cles and the secretory nerves on the gland-cells. In pathology trophic 
nerves are still spoken of in the sense indicated, but their existence has not 
yet been clearly demonstrated. As regards the experimental evidence, 
Snellen points out that the insensibility of the eye means a great deal in 
regard to the production of this variety of keratitis; an animal hits and 
injures its eye because it no longer feels the hurt. Feuer also calls attention 
to the desiccation of the cornea which results from the absence of winking 
after the eye has become insensible. Eberth, furthermore, invokes the lia¬ 
bility to microbic infection of an eye thus exposed. 

There is no necessity of having recourse to the trophic hypothesis in explaining the 
etiology of neuroparalytic keratitis. The explanation of Snellen, that the insensibility 
of the eye enables the usual causes to act without obstacle, appears to he the true one, 
thou-h he did not at the time of advancing this theory know of the important part taken 
by bacteria in the production of this condition. It is certain that the suppuration, often 
advanced as being characteristic and demonstrative of the neuroparalytic nature of this 
disease, cannot result alone from paralysis of trophic nerve-fibres. The seat of the disease 
being in the centre of the cornea and not within the inferior half, as in some cases of 
lagophthalmic keratitis, does not suffice for the making of an essentially separate morbid 
form (neuroparalytic) of it. It is true that the entire eye is insensible and that the pal¬ 
pebral opening is largely increased, thus exposing the coi 
is more natural that the centre of the cornea should be 

eye is the most remote from the blood-supply. In non-anaesthetic kera 
mos, the upper lid generally covers the cornea more or less. Thj^J 
to turn the eyeball upward and remove by this action any foreilC\^ 
present upon the cornea. Reflex lacrymation is not suppro§i(fij Ev< 

attempt to demonstrate the neuroparalytic nature of this>l£S*sc by basing their assertion 
upon the fact that suppuration may sometimes begii^iVhm depth of the eye, in the iris, 
while at that time the cornea may still he intact. Thi^^ry point, however, argues against 
their interpretation of it. Moreover, it is more tM^robable that the integrity of the cor¬ 
nea is more apparent than real. The neuropara hypothesis is accepted by most of the 

turbances resulting from paral*»s^pthe trigeminus might favor the outbreak of keratitis 
(Claude Bernard), but does n\y^lieve that they alone are capable of producing it. An 

alteration of the Gassei 
the trigeminus: the les 

^>nes the cause for the paralysis seems to be more central than the 

Gasserian gang^nVhl to have its location in the medulla oblongata itself.—Grave keratitis 
in typhoidal dise&es and keratomalacia in children are more or less comparable to neuro- 
paralytick^s^tis. The eyes in typhoid cases are seen to be widely opened, dry, and not 
protectorV^pwmking. This is certainly the result of a nearly complete insensibility of the 
e y e - sanie explanation holds good, from one cause or another, in the keratitis that 

oc in cachectic children. 

Vol. IV.—15 





Treatment .—In considering the treatment for this condition, it is impor¬ 
tant not to be carried too far by the neuroparalytic theory. Diligent and 
careful therapy may often save a little vision in an eye which would other¬ 
wise be hopelessly lost. Local measures, based on the traumatic theory of 
the disease, are urgently needed and efficacious. These consist in the use 
of antiseptics and the application of a bandage. The bandage protects the 
cornea from most traumatisms, from desiccation, and from infection by 
pathogenic bacteria. In some cases the bandage may be replaced by simply 
fastening the eyelids together by means of surgeon’s plaster. The dressings 
are to be renewed many times during the course of the day, and the eye 
is to be cleansed in a thorough manner by the use of an antiseptic solution. 
Iodoform is sometimes of value when the conjunctival secretion is marked. 
The treatment should be continued for a long while,—until the sensibility 
has partly returned. Even then relapses are to be feared. 

If it is possible so to do, the trigeminal paralysis should be treated. 
For this purpose the iodide of potassium is often indicated. One should 
not place too much confidence in the application of electricity to the cornea 
or in the use of hypodermatic injection of strychnine. 

Keratomalacia ( simple ); Xerophthalmic Keratomalacia .—Xerosis of the 
conjunctiva (see article on Diseases of the Conjunctiva) may extend to the 
cornea, which exfoliates and becomes overspread with a similar grayish, 
silky, and fatty covering. Wide-spread necrosis of the cornea is very apt 
to occur. There is no true suppuration, no hypopyon, and no pain. The 
symptoms are due mainly to a xerosis of the conjunctiv^but the corneal 
affection considerably aggravates the ocular disorder, aroNhiePioates that the 
general condition is seriously compromised. It isjwfcslase of infancy, and 
results from a cachexia, a species of kerato-comOfctivitis with anaesthetic 
lagophthalmos, upon which bacteria stamp aVg^cial impress. These mi¬ 
crobes (Neisser, Leber, Weeks, and otlie^C^wever, have not been fully 
identified. In infants, death, after a brij^jemy, is the rule (Leber) ; older 
children may escape a lethal result (Q&^V’ea, Kollock). Upon the evidence 
of an autopsy made by Virchow irMt case of this kind, von Graefe at¬ 
tributed the corneal disease to Aw&Jbtile encephalitis. By others, however, 
who have made autopsies unmp^fants so affected (Parrot, Jastro wits), the 
condition of the brain ha^A^n found to be normal. 

' A pernicious varietyx^* keratomalacia, but one which is not accompanied 
by xerosis of the conjunctiva, is the so-called “ simple keratomalacia.” It 
may be observe<B3p those children whose general nutrition is markedly 
depressed fro tatever cause, such as diarrhoea, typhoid states, etc. In¬ 
deed, in sririOhstances it is analogous to the type that is seen in the grave 
corneafN^w^plications of typhoid fever. Here the insensibility of the eye 
and ^Jlte aenutrition of the cornea afford a more favorable opportunity for 
n?i^r^bn3 infection. 

\ Treatment —This should aim at building up the strength of the patient 
& irough alimentation. Locally, antiseptics must be used and the eyes 



should be protected by a bandage. The nutrition of the cornea may be 
stimulated by the employment of hot compresses. 


The greater number of these affections are due to general constitutional 
disorders, and if they show the presence of microbes the infection is said 
to be endogenous. (See General Pathology.) As a general rule, the kera¬ 
titis begins in the tissue proper of the cornea. Such cases are, therefore, 
analogous to diseases of the fibrous tissues in other parts of the body ; and, 
like them, are of long duration and very often demand general treatment. 
They show no tendency to produce suppuration or lead the formation of 
corneal ulcers. 

(a) Parenchymatous Keratitis.—This condition is also known as 
interstitial keratitis and deep diffuse keratitis. It is a rather frequent dis¬ 
ease, having as its prototype deep non-suppurative keratitis. 

Symptoms. —A grayish discoloration appears in the periphery or in 
some other part of the cornea. This change of color soon spreads over 
the entire corneal membrane, which is infiltrated and its surface dulled 
throughout. At first the infiltration is translucent, like that seen in oedema 
of the cornea ; it then thickens and becomes of a grayish tint, which deepens 
until the iris is almost or quite obscured from view. Vision is greatly 
diminished, and may be reduced to mere perception of light. There is 
typical ciliary injection, usually without congestion of the conjunctiva. 
Lacrymation, slight photophobia, and ciliary pain are also present, for the 
disorder is always accompanied by iritis, or at least by ext^rab congestion 
of the iris. The anterior chamber is usually deepened,gM'the tension of 
the eye is frequently reduced. In subsequent stagesjsfimaHna may occur. 

The disease ordinarily attacks both eyes, eithe^Y^nultaneously or con¬ 
secutively. When a single eye is attacked the.q^kent should be apprised 
of the danger to the other. After twQ weeks, sometimes after 

several months’ time, the malady begird uHiisappear, starting with the 
periphery after tiny vessels have devel(tf5kl in the depth of the membrane. 
The clearing process may occupy mj^ months or even a whole year. Ex¬ 
amination with a strong magnifjQ&f lens under focal illumination will 
always show the persistence^v^ d^rtain diffuse opaqueness that is situ¬ 
ated chiefly in the centre of#™^cornea. Vision, though it becomes greatly 
improved, remains som^vljat impaired, as indelible spots of very dense 
tissue : true corneal 4 s(^roses too often remain behind. Such is the classical 
form of parenchymaKffs keratitis. Atypical varieties result (a) from vari¬ 
ations in the tjii^k^mng process or from a more copious infiltration in some 
places than^^^Sers; (6) from a more extreme vascularization (vascular 
form), and (c^from a predominance of the symptoms of irido-chorioiditis. 

UiMrftifyly Infiltrated Forms .—In the typical variety the infiltration, 
whi&h tVthe naked eye may appear to be diffuse, is with the aid of a strong 
copyex lens seen to be interspersed with a multitude of more densely affected 



points. This unevenness may be pronounced; the cornea may show large, 
irregular maculae of rather intense whiteness instead of the diffuse grayish 
tint which is seen in the more common variety. Some portions of the 
cornea may even remain comparatively transparent, and the infiltration, 
though it is always deep, may be only partial. Numerous small, deep in¬ 
filtrations situated in front of the membrane of Descemet, and in the centre 
of a rather transparent cornea, have been described under the name of 
deep, punctate syphilitic keratitis (Mauthner and others). (See also Differ¬ 
ent Forms of Deep Keratitis.) In rare cases, the more intensely infiltrated 
spots in the centre of the cornea may become ulcerated (Hutchinson, 
Treacher Collins). Intense infiltrations leave behind very dense and per¬ 
manent maculae, known as sclerosis corneas. 

Vascular Forms .—In these types the new vessels, which are developed 
in the cornea more or less in each case, arise from the deep pericorneal 
branches; they are so small that they are often visible only through a 
magnifying glass. In the regressive stage they remain for a long period 
of time permeable, though empty. Any irritation of the eye, however,— 
such as a clinical examination,—causes the blood to reappear in them 
(Hirschberg). Their walls remain as a permanent impediment to vision. 
Sometimes vascularization exists from the beginning, the cornea appear¬ 
ing uniformly red. These forms are very tenacious and leave dense opaci¬ 
ties. In the anterior planes of the cornea vessels may be given off by 
the superficial ciliary branches and elevate a large portion of the corneal 
epithelium in the shape of an epaulet. Some authors would regard this as 
a scrofulous variety of deep keratitis. 

Irido-Chorioidal Forms .—It has already beei^Mted that there is 
always iritis, or at least an intense congestion ofU^iris. In most, if not 
in all, cases posterior synechise, which may fe&pne complete and expose 
the eye to (secondary) glaucoma, are produf5$* In almost every instance 
there seem to be deposits on the. post^n^^urface of the cornea. Very 
often, especially when the affection oTTe of long standing, evident phe¬ 
nomena of cvclitis and chorioiditis0?observed. Chief among these may 
be mentioned the slaty shade q0he sclerotic around the cornea, which is 
so characteristic of chronic d^tis. This is due to impregnation of the 
sclerotic by the pigmeniNtfMhe ciliary body. Sometimes the sclerotic is 
infiltrated quite as IPO* *it is in scleritis. Subsequently ciliary or inter¬ 
calary staphylomateQn^y supervene when, in consequence of posterior syne- 
chise, the eye hfi^ecome glaucomatous. The corneal inflammation may be 
so hidden thafrtwe condition is spoken of as one of irido-chorioiditis. 

During^tVcourse of the disease, the ophthalmoscope reveals chorioidal 
affeetia^yV'specially about the ora serrata. Hirschberg holds that this 
occurs immost instances of parenchymatous keratitis, while von Hippel is 
iWe Specific in stating that it is found in sixty per cent, of all cases. 
iJally, autopsy has always shown the presence of iritis, cyclitis, and 
orioiditis or retino-chorioiditis. 



While the fact should be taken into account that, in all cases of this 
kind that are submitted to autopsy, the disease has been very serious and 
has destroyed the sight, it remains none the less true that, according to all 
appearances, parenchymatous keratitis is always accompanied by a greater 
or less inflammation of the whole uveal tract, especially in its anterior seg¬ 
ment. This affection of the uveal tract is by many considered to be the 
principal feature, the keratitis being, in their opinion, only a complication 
of the disease. 

Michel, in this connection, distinguishes two forms : in the one, the dis¬ 
ease commences with the corneal affection ; in the other, the corneal affection 
is absolutely secondary and consequent upon that of the uveal tract. 

Those forms in which irido-chorioidal phenomena are predominant are 
often distinguished by ciliary 

pains, which become most ^ IG - 14 - 

severe at night when the 
patient is in bed. 

Pathological Anatomy . — 

In the few cases in which the 
diseased area has been exam¬ 
ined anatomically (Fuchs, 

Brailey, von Hippel) vessels 
have been found traversing; a 
deep cellular infiltration on 
the cornea (Fig. 14), which 
increased in density as far as 
the membrane of Descemet. 

There was also an qedematous 
swelling of the cornea, which 
was more pronounced in some 
places than in others. The 
diffuse initial trouble seemed 
to be due, in part at least, to 
this oedema. The cellular in¬ 
filtrations extended to the ^^yPjichymatous keratitis (Fuchs). E, corneal epithe- 

irido-corneal ancrlp fthe nectiiN® 1 ^’ Bowmail ’ s membrane; S, tissue proper of the 
\ P B k "N^^rnea, showing a cellular infiltration which commences 
nate ligament), the iris,^an(P Hi the middle layers and increases progressively as far as 
-I t i -j | the membrane of Descemet ( D ), where it is most dense 

1 OOQy. Jliin Dl^^I^.l ($); g t deep vessels in the cornea; the membrane of Des- 

cells also covered tlia l^^crior cemet is undulated, owing to the unequal swelling of the 
p p , T r» corneal tissue; r, a collection of round cells on the posterior 

SU1 race ot the memHirine ot side of the membrane of Descemet. 

Descemet. D^QHme cases 

where the ekferash seemed to be of a scrofulous nature, there have been 
found areate or infiltration resembling tubercles (Fuchs), even with giant- 
cells i^QieVi (von Hippel and Zimmerman), in the cornea, iris, ciliary 
bod&ana chorioid. The last-named author claims also to have detected 
bacillus of tuberculosis in the affected portions. 

♦ /I . 



Etiology .—As has been already stated, parenchymatous keratitis has 
usually a constitutional origin. Moreover, with very few exceptions, it is 
an ailment of childhood and especially of adolescence. 

Since Hutchinson’s classical publication on congenital syphilis we are 
aware that this is the cause in most cases. In every instance in which 
parenchymatous keratitis is observed the parents’ history should be care¬ 
fully inquired into, and search be made for the concomitant symptoms of 
hereditary syphilis, such as remainders of old fissures, cicatrices at the labial 
angles or in the mouth and throat, swelling of the lymphatic glands, de¬ 
formities of the long bones (as at the crest of the tibia), flattening and 
enlargement of the root of the nose, atrophy of the upper jaw, strongly 
projecting frontal protuberances, etc. Hutchinson has called attention to 
two symptoms of hereditary syphilis which frequently accompany paren¬ 
chymatous keratitis,—namely, a certain degree of deafness (caused by otitis 
media) and a peculiar conformation of the teeth, “ Hutchinson’s teeth.” 
(Fig. 15.) Soon after their eruption the upper incisors of the second 

Fig. 15. 

Hutchinson’s teeth, occurring in congenital syphilis. 

dentition become narrow at their free margins. The slq$*sg shape becomes 
more and more pronounced until the teeth are cow^Jtecf into shapeless 
stumps. Sometimes these teeth and even thesuperior maxillary 
bone are rudimentary from their origin. The >©tn of Hutchinson should 
not be confounded with those which have^&ransversely striated surface 
(rhachitic teeth). As Hutchinson’s te^ChkWist in nearly one-half of the 
cases of parenchymatous keratitis, ^heriwpresence is regarded as pathog¬ 
nomonic of congenital syphilis. 

The coexistence of these teeth wi0fcie defective audition and the interstitial keratitis 
constitutes the symptomatic “ triad\jA Hutchinson, which is absolutely characteristic of 
congenital syphilis. NevertAjMJ the teeth may not assume this form in hereditary 
syphilitic keratitis and thev^^he only slightly roughened. In such cases it is well to 
give, if possible, attention t>4!fie ophthalmoscopic signs recently enumerated by Antonelli 
as being present in cons^iii£vl syphilis,—namely, a certain degree of pallor, sclerosis of the 
papilla, a massing*-oC«gment on the papillary border, a certain narrowing of the retinal 
arteries, and a ^S^Kfar state of the retinal pigment. These are not exclusively charac¬ 
teristic of cpurtSfoal syphilis, but their existence may confirm or establish the diagnosis. 

HutdVjXcV believed congenital syphilis to be the sole cause of parenchymatous kera¬ 
titis. rt^^klay admitted that other conditions may produce it, but that the hereditary 
syphilitic mrm constitutes, at least, one-half and perhaps three-quarters of all the cases; 
rnseh gives sixty-two per cent., Michel fifty-five per cent., Mauthner eighty per cent., 
grer sixty-four per cent., Silex eighty-three per cent., and Panas forty per cent. 
According to Parinaud, hereditarv syphilitic keratitis betokens that, at the moment 
OS of conception, the syphilitic virus in the parents has become somewhat attenuated. Mobile 




the preceding pregnancies may have all ended in abortion, this one terminates in the 
birth of a viable infant. 

Acquired syphilis but rarely gives rise to parenchymatous keratitis. 
The cases cited as such are not all authentic; many are examples of iritis 
or irido-chorioiditis, which have produced secondarily a deep lesion of the 
cornea. It is a curious fact that syphilis in the adult very rarely attacks 
the corneal tissue, though it so frequently affects the iris and even the 
whole uveal tract. 

Scrofula is certainly a cause of typical parenchymatous keratitis; Mac¬ 
kenzie even attributed to it all the cases of this disease. One must admit 
that in some cases tuberculous deposits have been found in the cornea. 
Usually the iris, the ciliary body, and the pericorneal zone of the sclerotic 
were also infiltrated by the tuberculous process at the same time as the 
cornea. In one case, described by Bongartz, there were tubercles in the 
sclerotic around the cornea and in the uvea. In this case the cornea showed 
only a cellular infiltration with vascularization. Some clinical observations 
of parenchymatous keratitis have been published in which the anterior seg¬ 
ment of the eye seems to have been the seat of tubercles. It appears also 
that tuberculous iritis may develop without the appearance of tubercles; 
lienee their absence does not prove that an iritis complicating an interstitial 
keratitis is not of a tuberculous nature. Clinical observations also show that 
tuberculous iritis with parenchymatous keratitis may be cured. Finally, 
some examples of parenchymatous keratitis, typical at least in the begin¬ 
ning, are occasioned by tubercles, situated either in the cornea, in the 
sclerotic, or in the iris. This tuberculosis seems to bo^w^ys of endog¬ 
enous origin. It would, however, be going too far to re^pf all the cases of 
non-syphilitic interstitial keratitis which occur in^^rculous persons as 
being due to a development of tubercles in the mifeybr segment of the eye. 

In children, small corneal phlyctenules, that peV^^ transient, may give place to a 
deep, diffuse, tenacious keratitis, which is analo»ouNto/he parenchymatous form. During 
the last two years the writer has, at interval^S^cated a young girl who has suffered in 
both eyes from large and tenacious infiltrati^ji? of the corneal limbus, and which were 
each time complicated by an interstitial k^titis. A portion of the infiltrated area of the 
limbus introduced into the eye of a rabmSSid not cause tuberculosis. Primary and exog¬ 
enous tuberculosis of the cornea, been studied experimentally, particular!}’ by 

Haensell and Panas, have been^^i^Seldom observed in man. A suppurating ulcer de¬ 
veloped from,eight to fiftee^^ij^lfter the inoculation. 

Rheumatism, goM. influenza, impaludism, uterine affections, and con¬ 
tusions of the cora^Cnave been named among the rare causes for paren¬ 
chymatous k^i^&jFs. These cases are, however, often atypical, generally 
consisting^ra^in deep infiltrations of a part of the cornea, with iritic 
complication^ or merely a tendency thereto. Some authors seem to include 
all tW mrms under the name of parenchymatous keratitis, but the writer 
tliiiik^tncorrectly. Still others speak of a “ parenchymatous keratitis” in 
cases of iritis or irido-cyclitis tliat produce secondary alterations in 



the endothelium of the cornea, with a certain degree of oedema. They also 
even call it by this name when, later on, sclerosis of the deep corneal 
lamellae has developed. Thus a physician may seem to have in his practice 
relatively but a small proportion of cases of parenchymatous keratitis due 
to hereditary syphilis. 

Animals may be attacked by an interstitial keratitis similar to the parenchymatous 
form which is observed in man. In the febrile disease to which many young dogs are 
subject may be observed a double parenchymatous keratitis consequent upon the general 
malady. Hennike has recently described this disorder as it is seen in bears. The particular 
pathogenesis of parenchymatous keratitis is not by any means satisfactorily known. 

According to Panas and Fournier, hereditary syphilitic keratitis should be regarded, 
not as a localization of the syphilitic virus in the cornea, but as an expression of a cachectic 
state or dyscrasia of the general system. It will doubtless be admitted that the utility of 
the iodidesj and even of the mercurials, in a disease does not prove that it is of a syphilitic 

As the malady is in many cases the expression of a general condition, it is thought 
that a pathogenic germ,—a microbe or other noxious substance,—has be^n transported by 
the blood-current, and, emerging in the pericorneal vessels, penetrated the cornea through 
the path of the interstitial lacume. This is certainly true in regard to cases of keratitis that 
are due to tuberculosis. Besides a tuberculosis of the uveal tract, there are found, at least 
in the anterior segment, deposits of tubercle in the sclerotic, around the cornea, and even 
in the cornea itself. 

In Bongartz’s case the cornea did not contain tuberculous deposits. The sclerotic 
around the cornea as well as the uvea was infiltrated by them, but the cornea itself did not 
show their presence. Yon Hippel and Zimmerman have published examples in which 
the corneal periphery alone contained the tuberculous elements, and yet the cornea was 
affected throughout. It seems, therefore, that tuberculosis may exert a noxious influence 
on the tissue adjacent to that which is affected. Special attention sh^^d be given to the 
toxines that are produced by the bacillus of tuberculosis, which i^^)e|)roduced through 
the cornea, even when only the sclerotic is infected with the It may also be be¬ 

lieved, with von Hippel, that the presence of tuberculousA^^in the periphery of the 
cornea so alters its vascular supply that a keratitis occurytA^ugh the failure of nutrition. 
The resulting lesion may be more or less analogous fotoKsJjorneal affections that are ob¬ 
served particularly in scleritis, and generally in t hqs ^aHe^tions which involve the sclerotic 
immediately around the cornea > 

In this connection should be cited the diflfoer&rtn of corneal affection, with oedema and 
vascularization, which results from section greater part of the posterior ciliary vessels 

(Wagenmann), or from ligation of the venyeN^rticosse (Koster). Wagenmann explains this 
form of keratitis a!$o by a failure of thj^jitrition of the cornea. Granting that iritis and 
chorioiditis are always present in parenhymatous keratitis, it might be supposed that in 
this disease the corneal affectioriSil^Ji tmalogous manner, was pr duced in consequence of 
changes in the uveal tract. TJjN^perimental keratitis of Wagenmann does not, however, 
appear to prove very mud'rti^/is regard. To produce it, the circulation in the major part 
of the uveal tract must b^u/ested to such a degree that the eye becomes phthisical, and it 
is well known tha^ tiijre is a corneal disease in phthisis of the eye, no matter from what 
cause it may arise^^\Wlesion does not seem to result primarily from the failure of nutri¬ 
tion in the cornits nourishing vessels are not concerned in this experiment. 

As a q^j^ValVule, attacks of irido-cyclitis do not give rise to deep keratitis ; they do 
so, howei^nyy when they produce notable deposits on the posterior face of the cornea, 
and (&)AwnS* they cause grave alterations in the sclerotic around the cornea. Although, 
in th^i^ter case, the corneal affection only slightly resembles parenchymatous keratitis, 
it cwisj’vcs mention in this place. Still, it must not be forgotten that, in the beginning 
plVjypical parenchymatous keratitis, alterations in the sclerotic around the cornea are not 
5w?n. The only conclusion which can be safely drawn from the experiments of Wagen- 



mann is that the nutrition of the corneal tissue depends—more so than is generally admitted 
—on the intra-ocular circulation, owing to the connection existing between the corneal 
vessels and those of the uveal tract. 

Diseases of the uveal tract may provoke an affection of the cornea in still another 
manner. It has been demonstrated by Leber’ that the absence of the corneal endothelium 
allows the aqueous humor to filter into the cornea and produce oedema and irritation there¬ 
in. The injection into the anterior chamber of any liquid except the physiological solu¬ 
tion of chloride of sodium and the saturated solution of boric acid injures the endothelium 
and causes irritation of the cornea; it may even give rise to a persistent sclerosis (Nuel). 
In affections of the iris and in irido-chorioiditis deposits frequently occur on the posterior 
aspect of the cornea which injure the endothelium and affect the deep corneal planes. 
(See section on Lymphangitis of the Eye , etc.) Even in the depths of the eye toxines may 
be produced which damage the endothelium and the tissue proper of the cornea-. It is not, 
however, in this manner that the parenchymatous keratitis develops ; most often it begins at 
some part of the corneal periphery, and is not at first widely diffused over the cornea. It is 
shown elsewhere that the parenchymatous keratitis frequently commences in the corneal 
tissue before the appearance of deposits on the posterior side of this membrane. In cases 
of intra-corneal tuberculosis, which are always accompanied by tubercles of the iris, it 
might be supposed that the posterior portions of the cornea would become infected by the 
bacilli. Nevertheless, in a case of iridocyclitis of very long duration, which had in its 
course produced a deep sclerosis of the cornea, the writer found tuberculous deposits both 
in the iris and in a fibrinous cellular exudate of the anterior chamber, but the cornea did 
not contain giant-cells. Proliferation of the endothelium and a diffuse cellular infiltration 
were also found in the deep corneal planes. In conclusion, the evidence at hand seems to 
show that tuberculous germs when present in the anterior chamber are not able to pene¬ 
trate through the membrane of Descemet, even when the endothelium has become altered. 

A remarkable example of corneal disease, which is due to the destruction of the endo¬ 
thelium, and which very much resembles parenchymatous keratitis, has been investigated 
by R. Dubois, who produced it in a dog which was made to inhale chloride of ethyl. The 
inhalation was continued forty-five minutes, during which period the aiiimal had to be 
revived two or three times. The cornea became completely opaque^m* appeared like 
porcelain throughout. It cleared up in the course of a week’s tiujS^he new growth of 
endothelium being reproduced from the periphery. 

Treatment .—As this is a constitutional maladvQis clear that its treat¬ 
ment should be general as well as local. Thq/fry&l treatment is, however, 
quite as important as the general, for it ^oijrVian prevent and cure the 
complications and the consequences of ^e cfisease—synechia and corneal 
scleroses—which are destructive of visi^j) and against which general treat¬ 
ment is wellnigh impotent. Jb 

The first indication in the looaQspatment is to keep the pupil dilated by 
atropine, in order that, afte*^«4 is obtained, posterior synechia may not 
diminish the vision or gh^ 0^ to glaucoma. As the treatment will require 
a long time, the myclr^tij) will produce some temporary intoxication, as 
shown by the dryne^yf the throat. Dark glasses or a shade should be 

rare cases m w 

e<5^>f the 

ordered for the pli/ft^TTobia. A bandage is required only in the extremely 


he cornea threatens to become ectatic or ulcerated. 

This tr^M^nt is sufficient in the early stages, when the symptoms of 
irritation fcinrintense. After one or two weeks’ time it is necessary to aid 
resorpjjftythe exudations and to avoid sclerosis of the cornea ; as all the 

^ ^ plAl 1 C OfU'DIIOlOC Ttrlll/lll 'Al IT AV* AHA TMm^AnAfi n HA m ama aw 1 Ann nivnt-A f i i^wy* 4-1'* ATT 

A * 

is agencies which favor these purposes are more or less irritating, they 
be used with caution. Among them are hot compresses, the pro- 



jection of hot-water vapor against the cornea, and the ointment of the 
yellow oxide of mercury. They should be used for a long period of time, 
from several months to a year, and in alternation with one another. In 
syphilitic forms the writer has obtained encouraging results from daily 
massage of the cornea with mercurial ointment. Injections of bichloride 
of mercury into the conjunctiva have recently been recommended (Darier, 
Gallemaerts, and others). After cocainization one or several drops of the 
corrosive sublimate solution are injected about a centimetre from the corneal 
margin, the injection being repeated a few days later, when the irritation 
resulting from the first one has disappeared. Substances thus injected 
penetrate into the cornea and even into the interior of the eye (Pfliiger). 
In a case in which ciliary injection showed that the second eye was also in¬ 
fected, the corneal affection first appeared in the immediate vicinity of the 
point of injection, and spread from this place until it became complete. 
Perhaps these injections should not be made in the early stages of the 
malady; at a later period, however, when the symptoms of irritation have 
diminished, their use has resulted in a marked clearing of the cornea. The 
writer has employed them only in the hereditary-syphilitic form, but from 
all appearances they would be equally efficacious in the other varieties. 
The solution of corrosive sublimate thus employed has been of a strength 
of one part of bichloride of mercury to one thousand of water, but still more 
concentrated solutions may be used. A 1 to 500 solution of cyanide of 
mercury seems to produce the same effect, and, moreover, has the advantage 
of being less irritating. De Wecker has recommended qjVre copious injec¬ 
tions, as much as one-half of a Pravaz syringeful.—^mpales of obstinate 
vascularization of the cornea peritomy is to be perfi^^d.—The application 
of leeches to the temple, which seems to be i^Kc&ted especially in the 
irido-chorioidal forms, is contraindicated w^dQlie general health is bad. 
—In those cases that are disposed to be^jM^jcfironic, it is scarcely, by any 
known means whatever, possible to pre\enj The formation of synechise, and 
in such conditions atropine may nmduce increased tension. Iridectomy 
may be beneficial in these glaucomaWs forms, especially during the decline 
of the disease. Repeated puuy({0jte of the cornea has been undertaken in 
the beginning of the affecti^VMIt without any very evident success. 

General Treatment— *®q£^syphilitic forms usually require specific treat¬ 
ment, but it should ^forgotten that the majority of these patients are 

already cachectic anc^J^it the administration of mercurials may be injurious. 
Their use is, hoover, to be recommended for patients of relatively robust 
constitution. ^FyWnally, from one to ten milligrammes of bichloride of 
mercury^hQtfa be given daily in pill form. To prevent salivation the 
mouth^m^vhspecially the teeth should be washed, many times a day, with a 
solution of the chlorate of potassium. For feeble infants, whether syphilitic 
(VSfciqdy scrofulous, a medication that is less depressing is preferable,— 
iodides, with substantial nourishment, and cod-liver oil. In the treatment 
f adolescents, hot baths of the entire body, followed by sweating in bed, 




will be found beneficial. The disease often appears in the second eye 
during the course of treatment. 

( 6 ) Different Forms of Deep Interstitial Keratitis. —There are fre¬ 
quently observed cases of deep keratitis, consisting of more or less circum¬ 
scribed infiltrations, that sometimes increase in size and somewhat resemble 
those of the parenchymatous varieties. The lingering course and the iridic 
complications are also the same as are seen in the last-named malady ; the 
two forms, however, can scarcely be mistaken for one another. The reac¬ 
tion is at times intense, though sometimes it is mild. In the former case a 
surprising clearing of the cornea eventually occurs. In the latter, indelible 
scleroses of the cornea may remain. 

Etiology .—After a chill, or sometimes following an attack of articular 
rheumatism, a rather large and deep infiltration of a dull color appears in 
the central portion of the cornea. This is attended with rather severe symp¬ 
toms of irritation (photophobia, lacrymation, ciliary injection, congestion of 
the iris, and iritis). These infiltrations may thus be caused by contusions 
of the cornea; they have also been observed in cases of malarial cachexia, 
influenza, gout, and syphilis. Such a deep infiltration, which is more or less 
diffused, may start from a small ulcer, especially a phlyctenule of the cornea. 
They are often found in the new-born, being caused by the application of 
the forceps. A deep infiltration of the cornea within its whole depth, which 
leads to corneal sclerosis, accompanies relapsing scleritis. Deep infiltra¬ 
tions which have no tendency to suppurate are usually the result of con¬ 
stitutional diseases. 4 

Treatment —The iris should be examined frequently^a^ct^tropine is to 
be prescribed if necessary. As discutients or resolvenf^tamn compresses, 
especially in the rheumatic forms, and hot baths feQbwed by sweating in 
bed, appear to be useful. If there be photopln^^^Hark glasses should be 
worn. The bandage is indicated only in cas^v^which there are notable 
abrasions of the surface of the cornea. 

(c) Lymphangitis of the Eye. —TlJ^c&naition has also been described 
under the names of descemetitis , aque^ygcapsulitis, deep punctate keratitis , 
and serous intis . Lymphangitis (^the eye, the last of the varieties of 
keratitis to be described, is sih^ed in the deeper planes of the cornea, 
but the iris, the ciliary boeJ\Afcld even the chorioid are always attacked. 
The affection is really a^s^rlpis inflammation of the entire uveal tract, the 
cornea being involved ^{il^ secondarily. The alterations of the cornea are 
the most striking, ai^it is for this reason that it has been heretofore ranked 
among the varieti^Syflveratitis. The corneal lesion here is a striking symp¬ 
tom of a pmfero / malady of the eye. The name deep punctate keratitis 
leads to coqJj^s^m with the deep punctate forms of true keratitis, which are 
situated in front of the membrane of Descemet. The term descemetitis is 
also WTtorgpct, for the same reason. The name lymphangitis of the eye seems 
moke appropriate (de Wecker). 

er concurrently with the symptoms of serous iritis, and perhaps with some 



discrete synechiae, dots appear on the posterior aspect of the cornea. These 
spots are situated in the lower half of the cornea, and are often grouped in 
the shape of a triangle, with the base downward. They are frequently 
very numerous (a hundred or more), and most of them have a diameter of 
only a fraction of a millimetre. The larger ones, measuring a millimetre, 
are situated at tiie bottom, the tiny ones are placed at the top. They often 
have a brownish, almost rusty tint. On a level with the larger spots the 
substance of the cornea is dim and its surface is sometimes slightly dull. 
The deposits on the posterior face of the cornea consist of migratory cells, 
of fibrin, of various granulations, of some pigment, and of altered endothe¬ 
lial cells (Knies). H. Snellen (junior) has found them to be largely com¬ 
posed of motile bacilli. If this observation be confirmed, it will be of the 
utmost interest. These deposits, some of which may exist on the crystal¬ 
line lens, proceed from the depth of the eye, from the iris, from the ciliary 
body, and from the chorioid (whence also the pigment is derived). They 
pass through the pupil into the anterior chamber, and under the influence 
of gravitation and the movements of the eye are precipitated upon the pos¬ 
terior aspect of the cornea. According to the experience of Leber, these 
foreign particles produce such injury to the endothelium that the aqueous 
humor may penetrate into the substance of the cornea and cause trouble. 
The eye may be glaucomatous, possibly from hypersecretion of aqueous 
humor and occlusion of the irido-eorneal angle through exudation. The 
exudations may be reabsorbed. On a level with the largest spots indelible 
maculse sometimes remain. 

Etiology. —Syphilis, rheumatism, gonorrhoea, and actions arising from 
the corneal matrix are capable of giving rise to thi^^ffdition. 

Treatment —It is necessary to treat the iritLOV^ropine may be contra¬ 
indicated, owing to an increase of tension in ft^eye. 

In the rheumatic forms hot baths, folWtad by free perspiration in bed, 
have given good results. For the glaucV^tous symptoms the local appli¬ 
cation of pilocarpine is first to be trmqtamd if this does not succeed corneal 
puncture or, better still, sclerotomv perhaps, even iridectomy should be 

The nature of this di^a/^y^ not understood for a long while, as the 
posterior synechise are ipw discrete and few in number. Similar de¬ 
posits, which are no^<\iAunerous and excessively small, are produced in 
most cases of iritis oV^ne posterior aspect of the cornea (H. Friedenwald, 
Dunn). These*^fij5)s are only capable of being seen with a strong convex 
lens of 20 to30jD. They generally disappear without leaving behind any 
trace of t^J^n^ibrmer presence. 

(d) Indelible Corneal Affections in Irido-Cyclitis.—In severe 

cases^Jf indo-cyclitis of long standing, especially when the sclerotic becomes 
fii^^n^ a ffected, traumatic and other causes sometimes gradually give rise 
^^a dense sclerosis of the cornea. This is situated deeply in the posterior 
apportion of the cornea, and most often starts from the periphery. It is not 



the sclerosis itself that demands attention, but the fact that it is associated 
with a grave malady of the eye, which is more deeply situated and which 
most often leads to destruction of vision. This deep variety of sclerosis is 
largely due to an overgrowth of the corneal endothelium, which arranges 
itself in layers and forms a lamiated membrane that more or less closely 
resembles the true corneal tissue. Landesberg has recently called attention 
to these formations, which are so frequently found in eyes that are enucleated 
on account of traumatism. The deep corneal lamellae are also affected in an 
irregular manner. Vessels may develop in the newly-formed tissue. The 
grave and lasting changes seen in hypopyon are due to alterations that are 
similar to those which have just been described. 

( e ) Post-Operative Affections of the Cornea.—Following operations on the eyes, espe¬ 
cially after an extraction of cataract, deep lesions of the cornea may he observed in one of 
two forms : 1. A diffuse milky thickening of the whole cornea, which leaves a cicatricial 
cloud. It is a result of the destruction of the endothelium by the presence of abnormal 
liquids, especially of corrosive sublimate, which have penetrated’into the anterior chamber. 
Even pure water may produce this affection. Only the physiological solution of chloride 
of sodium and, perhaps, boric acid solutions are inoffensive (Nuel and Cornil). The cornea, 
divested of its endothelium, becomes infiltrated with aqueous humor. 2. Perpendicular 
striae at the point of incision of the cornea. This is an oedema of the cornea produced by 
the folding over of its edges or only of its deep layers (Nuel, C. Hess). 



1 . Corneal Maculae 
nated permanent corne 
matory processes (ulce: 
pendent on simple tram 

are rare. 

Maculae resulting from Inflammation ofAhtNJornea. —The 
may be small or large. The latter swnofcimes undergo vi 
When faint, they are spoken of as rrw&mlee or nubeculae co 
very distinct, white, and tendinous,^dieyntake the name of le 
rosis of the cornea is also a term/Sr»ris applied to this condi 
macula is very dense. If thei^pw? been perforation, the ci< 
iris may become adherent macula, especially at the pup 

ery (adherent leucoma).^"*Th 4 anterior chamber is diminished 
is more or less obliteraretf. Adhesion of the iris is often 
black spot on the lj^SJna. 

macula, especially at the pupillary periph- 

Jhe anterior chamber is diminished in depth and 
.. Adhesion of the iris is often marked by a 

black spot on the Igft 

Large adho^ta&/( 

Large adhe^Aft/expose the eye to the danger of glaucoma. 

The mi Which result from ulcers of long standing may be flattened, 

forming ft >n the cornea. After extensive destruction of the cornea, 

gan^s^ be closed by a thin cicatricial lamella, which generally becomes 
iic\^V projecting cicatrix is rarely produced by hypertrophy of the 

ictival tissue or of the epithelium. 



Maculae consecutive to inflammatory processes are usually due to the 
presence of a cicatricial fibrillary tissue, which has not acquired either the 
microscopic or the macroscopic appearances of normal corneal tissue. (See 
Genwcil Pathology .) 

In time, especially when the maculae are exposed abnormally to the 
weather and to continuous irritations, they may undergo degeneration and 
become the seat for the deposition of substances which render them white, 
tendinous, and porcelaneous. The most common form of degeneration is 
the hyaline. Fatty degeneration and the deposition of lime-salts have also 
been noted. These deposits may become deeply diffused in the corneal 
tissue, or they may be superficial, subepithelial, or even intra-epithelial, 
when they are more or less circumscribed, giving a bosselated appearance 
to the corneal surface. 

2. Hyaline degeneration may affect the epithelium or the substantia propria of the 
cornea. The substance thus produced is refractive, and arranged as granular deposits of 
various sizes or as large irregular globules. The hyaline material is produced by a trans¬ 
formation of the albuminoids and is closely allied to the amyloid substance. It differs 
notably from the latter in not turning brown upon the addition of a mixture of iodide of 
potassium and sulphuric acid. Both are colored by aniline dyes, such as fuchsin and 
gentian violet. Sometimes, especially if the tissues have remained for a long time in 
Muller’s fluid, the coloring only takes place after the sections have been left in the staining 
solution for a considerable period of time. 

Fig. 16 is an example of hyaline degeneration occurring in the parenchyma of the 
cornea, described by Saemisch under the name of colloid of the cornea. Somewhat be¬ 
neath the capsule of Bowman ( E ) is seen a collection of these globules of various sizes (Z>). 
At m the degeneration is progressing. The hyaline deposits are manifest in the lamellae 
of the corneal tissue. These are not degenerated cells, as held by von Hippel. By becoming 
confluent, globules of various sizes may be produced. 

When the degeneration affects the epithelium the hyaline iWteriaJ may diffuse itself 
in the protoplasm of the cell. (See Bullous Keratitis.) In suo^v case irregular granules, 
analogous to those seen at m in Fig. 16, appear in the midatQyTne protoplasm. Hyaline 
degeneration occurs frequently in many of the corneal aflps^ns, and seems to be especially 
due to defective nutrition. It is found in filamentary ^Atiullous keratitis, in keratitis en 
bandelettes, in the so-called essential scleroses o^h&^rnea, in arcus senilis, and in pte¬ 
rygium. While not wishing to deny the existence fotty degeneration of the cornea, the 
writer would call attention to the great similarity in appearance of the hyaline masses and 
the fat-globules, and the ease with which e could be mistaken for the other. The 

deposition of lime-salts has been provecL4>u?Tt is well to remember that the hyaline sub¬ 
stance itself may become impregnated^*!? lime-salts. 

The corneal epithelium coveriiraNfe^cicatrices may undergo hypertrophy and become 
cornified, recalling to mind the^ra5&<rance of the epidermis. Sometimes the conjunctival 
tissues starting from the ngri^py of the cornea penetrate, as in keratitis en bandelettes , 
between Bowman’s memtraiA and the epithelium. Cicatrices of the cornea, more espe¬ 
cially those that have uncfefgone degeneration, are capable of giving rise to ulcers that 
are very rebellious to^J0tment and prone to undergo relapses. 

Bagius recentl(^e^cribed a case in which all parts of the cornea—the physiological 
and the path^?£c^, the epithelium, the proper substance, and the exudative particles— 
had underg^^N^Vis hyaline or colloid degeneration. 

ficial ulcers, especially in young people, may heal if cicatrization 
■apidly, without leaving any notable maculae. Surprisingly good 
i^ts are sometimes seen in the clearing up of large spots that are due to 



gonorrhoeal infection in the new-born. A loss of substance which extends 
as far as one-half of the thickness of the cornea, and especially when it is 
accompanied by suppuration and perforation, even if caused by traumatism 
aud cured aseptically, will leave indelible maculae. The same sequelae 
almost always result from deep infiltrations that have existed for a con¬ 
siderable period of time. The superficial and the deeper vessels of the cor¬ 
nea, especially after long-continued inflammation, form permanent maculae. 

Diagnosis of Maculae with Inflammatory Infiltrations .—Either of the 
three pathognomonic symptoms of keratitis—ulcer of the cornea, dulness 
of the corneal surface, and ciliary injection—may be absent in cases of 
maculae. The surface of a macula may be bosselated but not really dull. 
Maculae may be vascularized with a small amount of injection of the 
ciliary trunks, but no capillary pericorneal injection. A much more diffi¬ 
cult case is that of ulceration in an old cicatrix. In each case it is neces¬ 
sary to observe the inflammatory areola of oedema surrounding the dense 
infiltrations, which may for a long time persist around an intense macula 
resulting from ulceration. This oedema, indeed, may be more or less 
cellular in character and leave permanently a diffused thickening or a scar 
around a leucoma. The cicatricial areola is then distinctly limited by an 
irregular line bordering the transparent part of the cornea; the inflamma¬ 
tory areola gradually disappears in the cornea. This sign marks the dis¬ 
tinction between an old nubecula and a recent slight infiltration, especially 
in an eye in which new or fresh infiltrations (phlyctenules) occur. The 
surface of the nubecula is not dull. These old, faint maculae are white; 
while the recent cedematous ones are of a grayish shade. < 

Visual Disturbances .—Vision is more or less decrea&pdrmienever the 
macula encroaches upon the pupil, although it seldomrt^omes an obstacle 
to the reception of light into the eye. On the oa^’ary, light penetrates 
the globe freely, as in cases of mature cataract^^SC^ visual troubles result 
from the diffusion of light in the eye; eacioSWtricial particle becomes a 
refracting body, and the light is scattereclvJ^e that which passes into a 
room through windows made of ground^Shtss.—Again, irregularities of the 
cornea may complicate a macula: example, after granular pannus and 

phlyctenules of long duration tl^Shornea may resemble a cut diamond. 
From this condition prismq rations of the light (irregular astigma¬ 

tism) and even monocular DfiNc^pia may result.—The diffusion is less pro¬ 
nounced in cases in whimtfie maculae are denser and more opaque. Such 
a leucomatous macula^covering a part of .the pupil, diminishes the vision 
less than a slight ^A^iiubecula) under the same circumstances.—The in¬ 
flammatory ced^m^surrounding a true cicatrix usually disappears. When 
it has been <$t™fced in front of the pupil, its removal may be followed by 
a marked inb^ase in visual acuity. 

Iftteae be a small central macula, the patient may see best in a dim 
light aM al so after instillation of atropine, the improvement of vision in 
bfifiuhses being due to pupillary dilatation. 



Amblyopia resulting from maculae of the cornea may produce nys¬ 
tagmus, especially when they have occurred at an early age, as in cast s of 
gonorrhoea of the new-born, and are large enough to preclude useful vision. 
It is probable that in the absence of any distinct vision, the directing 
power of the fovea over the ocular movements being absent, normal inner¬ 
vation does not develop in the infant. Perhaps the centre of the retina 
remains functionally defective, as in congenital cataract. At any rate, 
nystagmus does not occur when the maculae are formed in adult life. 

The relative frequency of myopia in eyes having corneal maculae has 
been remarked by Chauvel. The common occurrence of convergent stra¬ 
bismus under the same circumstances even in emmetropic eyes is well known. 
Divergent strabismus is also sometimes produced in cases showing high 
degrees of myopia. The patient must closely approach visual objects in 
order to augment the size of the retinal images; an emmetrope with 
maculae corneae must make the same efforts of accommodation as the hyper- 
metrope. Convergence and accommodation, which are causes of myopia 
and convergent strabismus, are exaggerated. 

Treatment .—In some cases a macula may disappear spontaneously, par¬ 
ticularly if it be recent and not too intense. The clearing of all kinds of 
maculae is favored by means that are more or less irritating to the eye,—as 
hot compresses, steam, ointment of the yellow oxide of mercury, accom¬ 
panied by corneal massage through the eyelids, mercurial ointment, stimu¬ 
lating collyria, laudanum, etc. Electricity has been tried, but without 
much success. Scraping of the cornea or cutting off the superficial layers 
with a cataract knife has but little effect except in the ro^erhses in which 
the affection is limited to the superficial layers. Pe^Jytty should not be 
attempted. Perhaps subconjunctival injections e^antiseptic solutions 
merit a renewed trial. Kothmund long ago recorfflyfcnded the use of water 
under similar conditions. 

It has been attempted, after the exaZpV^f the ancients, to insert in 
a cornea that is completely leucomatou^a HttUon of glass, of celluloid, etc. • 
the essay, however, resting upon a p|0Mb logical absurdity.—In our day, 
renewed efforts have been made to^^ up a gap of leucomatous cornea with 
tissue that has been taken fro^^a transparent human or animal cornea 
(keratoplasty); the grafts A^^e^ome attached organically, but the tissue 
afterwards becomes cloud^VHid upon the whole the optical gain amounts 
to nothing. These attempts, inaugurated by Reisinger, have been repeated 
by a great number^f physicians (see vol. iii. p. 832). Yon Hippel, who 
seems to have pi*A^!i these experiments the furthest, proceeds in the fol¬ 
lowing manpq^^rle requires that the anterior chamber shall be present. 
Only a sinWl^iehtral disk is incised, not the whole cornea, as recommended 
by Reismg^; hence the membrane of Descemet and the deep corneal por- 
tions^Mtiin, and the aqueous humor does not bathe and infiltrate the 
transplanted piece or the edges of the wound. By means of a small tre- 
»e, von Hippel cuts a disk in the centre of the cornea, and afterwards 



removes it with scissors and scalpel. In this space he transplants a cir¬ 
cular piece of equal size, which has been taken, through its entire thick¬ 
ness, from the cornea of a chicken. This method is preferred to the one 
of inserting only a part of the thickness of the cornea of a dog or a rabbit. 
It is not necessary otherwise to fix the transplanted disk, which adheres if 
suitable antiseptic precautions have been taken. Both eyes are covered 
for some days with a bandage, and rest in bed after the operation is insisted 

In cases of superficial maculae the vision is not as likely to be improved 
as it is by the easier operation of the scraping or cutting of the cornea. 
Sometimes the wearing of a stenopaeic diaphragm, joined to an appropriate 
convex glass for near vision, may improve the sight. 

Iridectomy may accomplish two very useful objects,—the one antiglau- 
comatous, the other optical. In cases of maculae with adhesion of the iris 
glaucoma may supervene from well-known causes. The antiglaucomatic 
remedy consists in a large iridectomy, which is best made above. Eyes 
of this description should also be carefully watched to guard against 
the danger of glaucoma. An iridectomy, when made with the object of 
restoring vision, should, if possible, be small and by preference be placed 
inward. Of late years external iridotomy is preferred to iridectomy. A 
radiating incision is made in the iris, which has been released from the 
eye through a corneal wound. The iris is then replaced in the anterior 
chamber. It is necessary first to ascertain that the retina acts normally, for 
it may be detached or may be absolutely glaucomatous. Thie is done by 
examining the eye in the same manner as in cases of cataiwst. The optical 
gain is usually less than the appearance of the cornea seem to indi¬ 
cate. The reason for this is that the cornea appears transparent than 

it really is, when it is viewed over the shining bc^l^m of the iris, or pus 
may have become infiltrated either behind the^T^ftalline lens or near the 
ora serrata in the vitreous body. (See Hy^ppm.) Iridodesis (Critc-hett) 
and iridencleisis (see Operations ) are noi^onger performed, on account of 
the lasting irritation and even sympath^t^ conditions to which they some¬ 
times give rise. 

Tattooing of the cornea (see^yJQ. jii. p. 833) is done chiefly for its cos¬ 
metic effect (de Wecker). ^^Mris but rarely improved; when tattooing 
does accomplish this optigarturpose, it is brought about in the same way 
as through the stenopsel^jjjlit. After cocainization of the eye, the Indian 
ink may be inserted the aid either of a bundle of needles (Taylor) or 
by a single point ¥fd§hed in superficially and obliquely (de Wecker). The 
Indian ink and^&eales must be rendered aseptic by heat. Adhesions of 
the iris expAsh^Hie eye to the danger of infection, or at least to an irido¬ 
cyclitis. It 1 ^ usually necessary to repeat the tattooing on several occasions, 
a certi^tv)eriod of time being allowed to elapse between the applications. 

*$LKeratalgia .—Small cicatrices of the cornea, which usually result from 
traJmtic erosions, and not from ulcers, sometimes remain painful for 
IV Vol, IV.—16 





months or more. Ciliary pains, with lacrymation and ciliary injection, 
occur at intervals, often in the morning, and last for an hour or two. These 
attacks are neuralgic in character, in the height of which the epithelium of 
the cicatrix may appear dull. Internal remedies, such as quinine and antipy- 
rine, have but little effect other than of a palliative nature. Massage of 
the cornea with the yellow oxide of mercury ointment often leads to a 
cure (Gillet de Grandmont). In an obstinate case I would excise the cica¬ 
trix, which is probably strangling or pressing upon some nerve of the cornea. 

4. Dense maculse of incrustations of lead are sometimes produced from 
applications to the eye of collyria made with a solution of acetate of lead. 
Such particles may be eliminated from the bottom of an ulcer, but if, in 

the mean time, the epithelium 
Fig - 17 - covers them, they will be¬ 

come permanently embedded 
in that situation. Incrusta¬ 
tion almost always takes 
place in Bowman’s membrane 
(Fig. 17), and can be re¬ 
moved with that membrane. 
Collyria of acetate of lead 
should never be used in ul¬ 
cerative keratitis. 

5. Essential Sclerosis of the 
Cornea .—JjX the preceding 
paragraphs we have spoken particularly of corneal o] >es#which follow a 
loss of substance. Corneal maculae originating fefcy whatever cause are 
often described under the name of “ corneal sclObsis.” Here should be 
noted the maculae that are consecutive to p§^0^ and to parenchymatous 
keratitis, also those which result from vegetations of the corneal endothe¬ 
lium, and finally opacities that original^^L irido-cyclitis and in scleritis. 
Under the name of corneal sclerosis^jfcr excellence is described an affection 
in which the cornea becomes porcelains ike, slightly vascular, and irregular 
as to its surface. The affectioi*y$xtends from the periphery towards the 
centre, as if it were beingej^e||died upon by the sclerotic. This opacity 
is a consequence of certa^^Trms of scleritis, and lessens but little in the 
course of time. In the published cases it was due to fatty degenera¬ 

tion of the tissue oiMbl cornea # (Baumgarten); and in another to hyaline 
degeneration (A<i§e;hiele). In a word, it results from regressive metamor¬ 
phosis of the of the cornea and that of the cicatrix, and occurs in 

cases of iMjg-continued faulty nutrition thereof. These maculae, especially 
all tho&^^mch degenerate, are not capable of being cleared up, and when 
they^re aeep, as they usually are, the practice of corneal abrasion is of no 

\ 6. Ribbon-Shaped Affection of the Cornea or in the Form of Transverse 
lands .—£ 

Precipitation of lead on the cornea resulting from the 
employment in a corneal erosion of a collyrium composed of 
a solution of acetate of lead: E, epithelium; B, Bowman’s 
membrane; S, parenchyma of the cornea. The lead is de¬ 
posited almost exclusively in a granular form in Bowman’s 
membrane, and in thicker trails in its nervous canals. 

-Special mention should be made of a rather frequent corneal dis- 


Fig 18. 

W'*' 1 




/* ; 
d ■ 

, ** .»* 

<v - .? ■> * *«► 

^» * ; * < ■•■ •* ' ; 

V ;. » e 9 551 * * j 
/.»✓/"' £f 


M W V^::-w 

*‘Vt-;«vV : 

;\> n«„4 * 

V«lW /} I • 

vV, -A it 

I I 


fcr ! :>: 

/ ; V$, S\: 

v 4 ' 

y * 4 ;•, A V %*< 
A* V’*\V ;«*« 

y « ♦***■.V *** 

, •( 1 * v o* * 

/■: v" o-;- ^V;U 

C; z> 

11 I 

degeneration of the corneal epithelium in the form of inflammation occurring in hand 
shai^fcff'ection of the cornea. T, normal corneal tissue; D, Bowman’s membrane; n. normal epithe 
h, hyaline globules in the abnormal conjunctival tissue. 



ease which was described by von Graefe under the title of “ Bandformige 
Keratitis.” On a plane with the palpebral slit a grayish or somewhat 
yellowish, non-vascularized inflammation appears, which extends trans¬ 
versely across the cornea; its surface is finely granular, or rough like 
granite, and rather dry. The affection generally begins at both extremi¬ 
ties of the horizontal diameter, though it sometimes starts in the middle ; 
both extremities, however, remaining transparent, somewhat as in arcus 
senilis. The eye thus attacked is always more or less irritated. The 
malady occurs most frequently in patients who have suffered for a long 
time from irido-cyclitis or glaucoma. It is then called “ secondary.” 
There is also a “ primary” form, which attacks eyes—either one or both-— 
that do not appear to be otherwise diseased. According to von Graefe, eyes 
suffering from the primary variety often become glaucomatous and should 
always be regarded as being predisposed to glaucoma. Nettleship includes 
acute cardiac affections and renal disorders as causes of this ribbon-shaped 
affection of the cornea. Nettleship and Goldzieher have found deposits of 
hyaline globes similar to those previously mentioned as existing in certain 
corneal cicatrices under the epithelium. For this reason the alteration may 
be looked upon as rather superficial. It appears that hyaline deposits may 
later on become the seat of calcareous concretions. 

In a rather atypical case of the secondary form, the writer found on the surface globu¬ 
lar hyaline masses under the epithelium and hyaline degeneration of the cells composing 
its middle layer, identical with that which has been described as a priman\ilteration in 
bullous keratitis. We have been inclined to view this degeneration as tfc^rearoause of the 
disease. Fig. 18 represents, in our opinion, the primary alterations wld^Niecur in cases of 
corneal inflammation due to band-shaped affection of the cornea. a^^jWglaucomatous eye 
was enucleated because of constant pain. Under the epithelifl£?y in Bowman's mem¬ 
brane, may be seen a peculiar conjunctival tissue, non-vasci^i%/m)or cells, with a clear 
intercellular substance, somewhat resembling the mucous/rtSne. It not only insinuates 
itself under Bowman's membrane and the epitheliun^tl^gso penetrates into the latter 
in the form of cylinders and elevates the surface* ii\§£^ll protuberances. Its general 
clinical appearance recalls slightty that of an epittf&ioma, but it bears no resemblance to 
pannus. In Fig. 18, at h may be seen some hvall^globules, which, however, were more 
numerous in other portions of the growth tl/3L in that chosen for the illustration. The 
abnormal conjunctival tissue undergoes M^jme degeneration, and may later on become 
infiltrated with lime-salts. Subsequqnti^|tl£/hyaline formation, primarily subepithelial, 
seems to be able to invade the supe^^^Hayers of the tissue proper of the cornea. This 
explains the fact that certain au^c^^ave described a hyaline degeneration that is situated 
deeply in the cornea. C J 

As for treatmenLJ&jtling can be hoped for a clearing up of the maculae. 
If the eye be nafeAmaurotic, scraping of the cornea (see vol. iii. p. 821) 
may be bene©A^as the reformed tissue is ordinarily more transparent 
than the macuQv In the primary forms atropine must be avoided. Miotics 
should b^jn’escribed, and if the ocular tension be augmented, iridectomy 
will <|>e o^iriy indicated. If vision be wholly lost and the eye is painful, 
reliejQsay perhaps be given either by enucleating the eye or by reducing it 



7. Arcus Senilis ; Gerontoxon .—In old age, and earlier in certain fami¬ 
lies in which it is hereditary, a whitish ring appears on the circumference 
of the cornea; it is larger above and below, is strongly delineated at its 
periphery and does not wholly reach to the limbus ; towards the centre of 
the cornea it becomes imperceptible. This arcus senilis, which causes no 
unfavorable symptoms, is the result of a hyaline degeneration of the sub¬ 
stance of the cornea, especially of the superficial planes. It was formerly 
believed to be due to fatty changes, but this is not the case. The presence 
of an arcus senilis does not interfere with, or check, the cicatrization of the 
corneal incision made in the extraction of a cataract. 

8 . Congenital Maculae of the Cornea .—It is by no means exceedingly 
rare to find in new-born infants, without other anomalies, maculae on one or 
both corneae. They are ordinarily situated centrally. Now and then there 
is at the same time an anterior synechia. Frequently, the cornea is un¬ 
usually small,—microcornea. Corneal staphyloma is sometimes congeni¬ 
tal. It is not always known whether these anomalies are due to vicious 
embryonic development, or to an intra-uterine corneal disease. Either 
cause appears possible. 


Staphyloma cornese is an ectatic cicatrix composed chiefly of the iris 
and, in varying proportion, of the tissue of the cornea, or of cicatricial 
tissue which has replaced that of the cornea. The iris usually forms the 
largest part of a staphyloma. It is always consecutiy^to a perforation 
with more or less extensive destruction of the corn^^ Staphylomata are 
divided into partial, which occupy only a portion M^&re area of the cornea, 
and total, which includes the whole area of the R&ptea as far as the sclerotic. 
Partial staphylomata have a tendency to de^flwinto the latter form. 

1 . Total Staphyloma .—A total stanbw^a is most frequently consecu¬ 
tive to an almost entire destruction qf &i£>cornea. It is formed at first by 
the iris, and is then reinforced at tEe&eriphery by a remnant of the corneal 
tissue. The iris is transformecLiiW a fleshy membrane, and afterwards 
into a cicatrix more or less^tfrM covered in front by epithelium. This 
cicatrix bulges more andbeing pushed forward by the aqueous 
humor; it is first grayishMken white or slate-colored, this being due to the 
pigment of the iri|pa>H5een by transmitted light. The ectasis may be 
globular and resemOkra grape. Its surface may be bossed, and strength¬ 
ened in parts Ts^^enser cicatricial ridges. If the staphyloma was at first 
partial, beingX^ntrally located, it may become conical, its periphery being 
reinforc^N^v thicker vestiges of the cornea. The surface of the staphyloma 
is travc^^a by vessels. The iris adheres to the remnant of the cornea as 
far *a4 the periphery, there being no longer any anterior chamber. (Fig. 
ISSjp The eye is always more or less hard. As a sequel, the outer layer 

the staphyloma frequently thickens, chiefly in the centre; at other times 
the latter is thinner. 



The ectasis becomes larger, is always accompanied by irritation, drag¬ 
ging of the tissues, ciliary pains, etc. A hernia appears between the lids, 
which no longer cover it. Then the epithelium may thicken, and more or 
less resemble epidermis. The wall may later undergo all the degenera¬ 
tions described when treating of corneal opacities. Thus exposed to attacks 
of every sort, the staphyloma may become ulcerated and perforated. The 
opening closes, and distention reappears. A panophthalmitis or a hemor¬ 
rhage after perforation may lead to phthisis bulbi. The sclerotic may take 
part in an ectasis, the eye becoming buphthalmic, especially in children. 
(Fig. 20.) 

Vision is always abolished, and finally the sensibility of the retina be¬ 
comes completely extinct, most frequently through glaucoma. A glauco- 

Fig. 20. 

Fig. 19. 

Corneal staphyloma of a 
more or less conical shape. 
The suspensory ligament is 
stretched or expanded. The 
crystalline lens is catarac- 

Buphthalmos in consequence of a#Sbmeal ulcer 
acquired in infancy. All the diameWraf tWe eye are 
increased. There is adhesion of th^raVto the cornea 
throughout its entire extent. /SjJCsuspensory liga¬ 
ment of the crystalline lens^^n-etched. The vit¬ 
reous humor (C V) is sepaniftCKfrom the fundus by a 
liquid exudate (D), bu^^Vdslill adherent to the ora 
serrata. There is_a ^Stijpbfnatous excavation of the 
optic nerve. 

j is a glatico* 


matous excavation of the optic nerve i^Wten produced. The vitreous 
humor becomes softened and reabsorbed.x^The chorioid, the retina, and the 
ciliary body undergo atrophy. TJ^^Iy stalline lens may have been torn 
loose and removed at the time ofiwe^erforation ; if not, it becomes catarac- 
tous. It may also be dislo&Ap; but even in cases of buphthalmia it is 
sometimes kept in place^bj^uie greatly elongated suspensory ligament. 
(Fig. 20.) Kjr 

2 . Partial Staptqfijnpa .—Partial staphyloma is brought about in the 
same manner as staphyloma. It results, however, from a more cir¬ 
cumscribed l^™gNof the iris. Simultaneously with the ectasis of the 
cicatrix th^^^fciounding cornea yields to the intra-ocular pressure and 
forms a cotae, the apex of which, centric or eccentric, is the cicatrix. The 
iris iSvS™Tjto be seen through the cornea, and there may also remain a 
littl^^f the anterior chamber. A certain degree of vision exists in cases in 
the pupil is not entirely involved or covered by the cicatrix of the 




cornea, or it may be afterwards lost by glaucoma. The ectasis often 
increases and becomes general and more conical. (See also Fistula of the 
Cornea .) 

A perforation of the cornea, most frequently caused by ulceration and 
suppuration, is occasionally the cause of staphyloma. It is most to be 
feared in cases of large ulcer, the thinned borders of which cannot resist 
the intra-ocular pressure. Sudden efforts of every kind are factors which 
prevent a cicatrix from becoming firm, and even cause one which was at 
first flattened to become ectatic. 

A large thinned cicatrix yields to the normal pressure of the eye. The 
mechanical conditions (extensive anterior adhesion of the iris), however, 
are such that from the first the eye is glaucomatous. If, on account of 
the easy filtration of aqueous humor through the thin cicatrix, the tension 
is not at once exaggerated, it will soon become so. While a portion of 
the anterior chamber may still remain in the beginning, it generally be¬ 
comes at last completely obliterated. A staphylomatous eye is always a 
glaucomatous one. 

Treatment —Every prophylactic precaution should at once be taken. 
This includes relative rest in case of prolapse of the iris, and prohibition 
of all fatiguing corporeal labor, even for a long period of time after cica¬ 
trization has occurred. An eye in which there is a large cicatrix of the 
cornea, with adhesion of the iris, must be watched, and, if possible, an iri¬ 
dectomy should be made as soon as the tension increases, or even before. 

A partial staphyloma can be cured with the preservaJ^Ai of a moderate 
amount of vision, but the transparent parts of the c^tOTsamave lost their 
curvature and are always more or less dull. WhiwC^tfine may be useful, 
atropine must certainly be avoided. There shoul^Nbe no delay in making 
a large iridectomy combined with excision oS^i/elongated fusiform piece 
of the cicatrix, if this be of considerably^© The latter is usually very 
thin, and in reuniting the edges of the ^ojjnff greater thickness should be 
obtained. Transfixion is made witff^ataract knife, and excision is then 
performed by means of forceps and seizors. In somewhat pronounced cases 
the excision may be followed Krajbrneal suture (Kenneth Scott). As this, 
however, deforms the cornea>th^ conjunctival suture is coming to be pre¬ 
ferred. That operation ft^fformed as follows: From the conjunctiva be¬ 
hind the wound are t^<jQwo flaps, the borders of the ulcer having been de¬ 
prived of their epitlMkfm by scraping ; these flaps are slid across the cornea 
and sutured. T<jf?Jonjunctiva thus adheres over the wound and strengthens 
the cicatrix, shrinks and atrophies on a level with the portion of 

the corne^thar has been covered by epithelium. Further treatment consists 
in restN^l ¥ the wearing of a compression bandage for a month longer. 
The^gVxcisions should more frequently than they are be combined with an 
irfc©tohiy, which is made as large as possible. 

V Total staphyloma requires a more energetic intervention to relieve the 
©jpain and to remove an awkward ectasis. A simple incision is of no use 



whatever. If the staphyloma be not excessive, it may be treated by cutting 
a piece from the side, as in case of partial staphyloma. Staphylomata of 
good size require a larger incision, including the entire circumference of the 
cornea and even extending into the sclerotic. As loss of the media of the 
eye, hemorrhages, and purulent infection may result from the larger wound, 
its lips must be reunited with sutures. For that purpose Critchett’s opera¬ 
tion has for a long time been much in vogue. Three large needles, threaded, 
are passed vertically through the eyeball, half a centimetre from the edge 
of the cornea, and are left there to support the ball. Then, with a cataract- 
knife passed in front of the needles, a large horizontal piece, the extremities 
of which are in the sclerotic, is cut out. Forceps and scissors are used to 
assist in cutting away the piece as far as the sclerotic edge. This done, 
the threaded needles are passed wholly through, and the threads are tight¬ 
ened. The result is a horizontal cicatrix with two projecting extremities, 
which may prevent the wearing of an artificial eye. Therefore preference 
is now given to excision of the staphyloma with the purse suture of the 
conjunctiva, either according to the method of Knapp or in accordance 
with that of de Wecker. (See Operations , vol. iii. p. 828.) The two 
operations are still, however, sufficiently complicated, and the writer often 
contents himself by operating in the following manner: Around the cornea 
a thread is stitched well into the conjunctiva. The staphyloma is then 
excised, and the thread tightened. The operation is easier and gives a 
regular stump, well adapted to receive an artificial eye. 

The evisceration of the eye, or enucleation of its contents, by means 
of a scoop, after excision of the cornea (Graefe, Bunge)*d^m too small a 
sclerotic stump and has no cosmetic advantage over thgngmacleation of the 
eyeball. Healing takes place but slowly. In somea^ihe stump shrinks 
to a small size and, above all, the liability to syrntf^ytetic ophthalmia seems 
to be greater after this operation than after ennsfeafion. Various attempts 
are nowadays made to preserve a larger stun/pNftjJch will give more motility 
to an artificial eye. Besides the operatior&>f evisceration, already mentioned, 
it has been essayed (Mules et al.) to ^jjose within the sclerotic spherical 
bodies of glass or bone (see Oper^^ns), also a blood-clot (Venneman). 
This practice has not met with ^tSral favor; healing is always delayed, 
and the presence of a foreig^AQpdy enclosed in such a manner does not 
seem to be devoid of dangers 

Enucleation of the e\ r ^ sliould be quite exceptional, and should be re¬ 
served for cases of^ bj^htnalmos, which present conditions excluding pro¬ 
tracted post-operafci^Treatment. At first, a stump causes excursive move¬ 
ments of the* q™Mal eye ; afterwards the absence of the eye produces a 
stagnation^N^ liquids in the orbit, and painful conjunctivitis. 

Tattooin^of a staphyloma is useless, and exposes the eye to infection. 


may here be made of intercalary staphyloma , which is in reality an ectasis 
~ cornea and not of the sclerotic. In a glaucomatous eye, often in consequence of 
yclitis, a grayish-black ectasis may sometimes appear between the corneal periphery 



and the sclerotic. The resulting staphyloma is ordinarily spoken of as a staphyloma of the 
sclerotic, and which is then differentiated from the ciliary staphyloma of the sclerotic. 
(See Ciliary Staphyloma.) It is noticed that the ciliary vessels do not pass above such an 
ectasis, but that they spread over a ciliary staphyloma. In reality, this form of staphy¬ 
loma, which is called intercalary because it seems to develop between the ciliary body and 
the periphery of the iris, is an ectasis on a level with an irido-corneal glaucomatous 
peripheral synechia. (See Fig. 21, X.) It is from adhesion of the iris to the cornea that the 
latter becomes more or less softened, so that it here yields to the increased tension. There 
is, therefore, an ectasis of the corneal periphery, with the neighboring portion of the scle¬ 
rotic, on a plane with the canal of Schlemm. The ectasis is covered by the iris, which is 
always atrophied at this plane; it is not the result of an ulcer, but of glaucoma, either 
primary or secondary. 

Congenital Corneal Staphyloma .—In the new-born is sometimes seen a corneal ectasis, 
which is covered on its posterior aspect with atrophied iris. In an eye of this kind which 
is in our possession the lesion resembles a corneal staphyloma following an ulcer ; the crys¬ 
talline lens is in an embryonic stage, its fibres appearing like large cells. The ciliary 
muscle scarcely exists. There is no glaucomatous excavation of the papilla, and the retina 
and the chorioid are atrophied towards the equator of the eye. There is a rudimentary 
hyaloid artery, and the ciliary processes—properly speaking, folds of the retina—reach to 
a point behind the crystalline lens; there is also a pyramidal cataract. 

3. Fistula of the Cornea , or, rather, Fistulous Staphyloma .—A perfora¬ 
tion of the cornea may for a week or more fail to close without deserving 
the name of corneal fistula. This name is properly applied to a perfora¬ 
tion of the'cornea which is hindered from closing by an epithelial covering. 

Fig. 21. 

Fistula of the cornea: C, spot where thebreaks through; A , B, limits of the cicatricial tissue 
of the cornea; F, intra-corneal gap lined /lN^ris-pigment; Y, dehiscence or split in the cornea; L, 
posterior corneal plate, drawn backvwir|^uH^ward by the sphincter of the iris (plainly visible); the 
iris, or rather its sphincter, adher^'hjCrextremity of this corneal plate; 0, opening through which 

the fistulous gap of the cornea 
ber; C. C., ciliary body; X, 

icates with the posterior chamber; A. C.H., anterior cham- 
nd peripheral glaucoma, producing synechise of the iris. 

Such cases in realigUnever occur. Czermak observed that the simulated 
fistula is only pgfP^Hfic, and that it consists of cicatricial tissue in which the 
sphincter o£ tff^pupil is so involved that firm cicatrization is prevented. An 
an atom isfSS^Vimi n at io n of two eyes of this kind confirms Czermak’s views. 


After central perforation, there is always danger of a central cicatrix 
cornea, with partial or total adhesion of the pupillary sphincter, 
leanterior chamber still exists to a great extent, at least in the early 
^es. The cicatrix, which appears as a black spot on the iris, becomes 



ectatic. The cornea is thickened and infiltrated, and there develops a small, 
faint, conical staphyloma, of which the cicatrix is the centre. Later, the 
cicatrix breaks down, the staphyloma gives way, the opening closes, and 
the staphyloma is reproduced. This may be repeated a number of times, 
until, finally, the eye is completely lost by glaucoma. 

In a case of this kind the writer found, anatomically, at the location of 
the cicatrix an excavation of the cornea lined with pigment of the iris. 
(Fig. 21, F.) A vestige of the latter had been taken into the cicatrix. As 
shown in the illustration, the sphincter of the pupil adheres to a posterior 
lamina of the cornea, and draws it backward and inward to such a degree 
as to detach it from the rest of the cornea, and to narrow the opening of 
the excavation. 

Treatment .—Where there is peripheral secondary anterior synechia of 
the iris, it will be necessary to attempt an iridectomy, and especially a scle¬ 
rotomy. One may even have to excise or to incise the small central cicatrix, 
for the sake of obtaining a more solid reunion of the edges of the fistula. 
As in the case of partial staphyloma, the conjunctival suture is to be recom¬ 
mended very highly. Simply cauterizing the cicatrix has not been attended 
with favorable results. 



(a) Kerateetasia is an ectasis of the cornea alone, the iris not being 

involved in it, as it is in staphyloma. A partial kerate*^\sia may result 
from an ulcer which after cicatrization leaves a thin cXwi*; this is rare, 
however. A keratocele is from a certain point of kerateetasia. A 

cornea extensively infiltrated, as in granular paifims or parenchymatous 
keratitis, may become ectatic throughout. Th^Qfrvature of the centre of 
the cornea is then increased, and from tlu^Jipcrease an appreciable degree 
of myopia may result, correction of whic^jji useless owing to an impair¬ 
ment of corneal transparency by the e^fasia. 

(b) Keratoglobus is a result not o£^keratitis but of infantile glaucoma 
(Dufour). The infantile corlmjjjQfields and becomes distended. It is 
ectatic all over, thin and tra^W^ent, with augmentation of its radius of 
curvature. The anterior ber is deepened. Vision is diminished or 
even abolished by tho^^^coma, and there is often an excavation of the 
optic nerve. The ey^s/sometimes enlarged in all its diameters (hydroph- 
thalmos). (See (jQfacoma .) 

(c) Keratocd^p .—From some unknown cause, the centre of the cornea of 

a young pe^Kmay grow thin and be pushed forward. The cornea becomes 
conical, riphery flattens, and its centre increases in curvature, but re¬ 
main s^foansparent. Vision is impaired, and in extreme cases may even 
be destroyed. (Fig. 22.) In the beginning the patient complains 

JtfSLnly of symptoms of myopia. As the cone enlarges the sight is so much 

0vl ;erfered with that it is no longer improved by spherical glasses, and, if 



irregular astigmatism supervenes, it falls to a point at which reading be¬ 
comes impossible. Through the ophthalmoscope the fundus of the eye ap¬ 
pears deformed. When illumined from a distance by the mirror, the pupil¬ 
lary field contains a dark ring which surrounds the centre of the cornea. 

Fig. 23. 

Keratoscopic images in a case of keratoconus 

Skiascopy shows a stronger myopia in the centre thanMjf the periphery. 
Keratoscopic images, small and even regular in the^pitre of the cornea, 

radiate to the periphery. (Fig. 23.) ■ . 

In the beginning of the disease the defia™yy of the cornea is rather 
difficult to recognize. When only one eye\js/ifrected the observer would 
naturally think that he was dealing witlX^case of myopia combined with 
a high degree of astigmatism. The entasis, however, becomes more and 
more pronounced. In a progressmsgfrse it may be plainly seen when the 
eye is viewed in profile. (Fiai^S**) An early diagnosis may be made, 
however, by observing with Ophthalmoscope the circle of obscuration 
around the centre of the cornea (Bowman). 

Although the cornea%yJpears transparent, there is often found by focal 
illumination a slight ©rabidity, which becomes more manifest as the disease 
advances. The edrhral centre is distinctly thinned and is easily depressed 
by a probe. ♦ImSha-ocular tension is normal or slightly diminished. The 
eye itself isAot> irritated. In most cases both eyes are attacked, the second 
one considerably later, sometimes a year or more after the first. In the be- 
ginni^y^ ectasis is quite small, but it slowly and gradually augments 
dupHigseveral years’ time, and finally becomes stationary, when the vision 
ry much impaired. 

Fig. 22. 

Fig. 24. 



The cause giving rise to this condition is unknown. The affection ap¬ 
pears most frequently between the ages of fifteen and thirty years. A feeble 
constitution has been noted in many of the patients that have been af¬ 
fected. Bowman found keratoconus in several members of the same family. 
Women are more liable to the disease than men. 

Spontaneous rupture of the thinned cornea never occurs. According to Bowman, an 
abnormal transudation of the aqueous humor takes place through the thinned cornea, so 
that the balance between the resistance of the cornea and the intra-ocular pressure is re¬ 
established. This explains not only the arrest of the ectasis hut also the cause for the 
hypotonus or decreased tension. 

The method of production of keratoconus is still unknown. On anatomical examina¬ 
tion, Hulke found the membrane of Descemet intact in the centre, and an accumulation of 
lymphoid cells in the superficial layers under Bowman’s membrane. Brailey describes intra¬ 
epithelial lacunae as existing in the extirpated central rings. The stroma was infiltrated 
with elongated cells. Rampoldi observed the same cellular infiltration of the stroma, and, 
in addition, found drops of myelin in the epithelium, associated with the absence of the 
membranes of Bowman and Descemet. It is highly probable that the greater part of these 
alterations are the result, and not the cause, of the ectasis. The cellular infiltration par¬ 
ticularly, which shows itself in the central lesion of the cornea, evidently does not exist in 
the beginning, and even the thinning of the corneal membrane, apparently the cause of 
the ectasis, seems partly to be one of its effects. In the experiments of His a central kera- 
tectasia was produced by incising the membrane of Descemet with an instrument intro¬ 
duced into the anterior chamber. Elschnig, who has recently taken up these experiments 
again, compares a keratoconus to an aneurism in which the primary lesion is a lacuna in 
the elastic tunic of the artery. In his case there was originally a lacuna or an attenuation 
in the membrane of Descemet. Before him Tweedy supposed keratoconus to result from 
an arrest of development of the centre of the cornea. 

In the treatment of conical cornea efforts have beq e to neutralize 
the irregular refraction by optical measures or to to the cornea its 
normal curvature. 

Optical Treatment .—In the early stages, a^TSyterable improvement of 
vision may be obtained by the aid of apw^Jnate concave glasses, com¬ 
bined, if need be, with cylindrical len^s!V%his correction, however, does 
not give satisfactory results in advafoecreases. Glasses with hyperbolic 
curve have been recommended by (0*ehlmann, but they are not of much 
value. The abnormal curvatur^yf the cornea is not spherical, nor in 
reality conical, but it is hyperl^oW}. 

A long time ago Sir^qfiy Herschel proposed to correct the refraction 
by placing over the cortfSk'-a transparent shell or cup,—a “ contact glass.” 
The suggestion has fec&vfly been repeated by Fick and Kalt. Sulzer im¬ 
proved the cup Jetting the glass. When the introduction of air-bubbles 
between the co*^T and the shell is avoided, a notable improvement of 
vision is ob|Si|ied. Unfortunately, the contact glass is a foreign body 
which i^^Nbng tolerated. 

Favomble effects have always been obtained by the employment of a 
st^n^fe^c slit, either alone or combined with correcting lenses. G. Mackay 
^s recommended an opaque diaphragm pierced with a series of small open- 
s. H. Snellen has recently, by means of a special variety of the steno- 



paeic slit, increased the vision tenfold. In this form, which had already 
been recommended by Hensen, the horizontal slit, passing from left to 
right, narrows almost to a point at the centre of the opaque disk. Words 
viewed through the middle of the slit are distinctly seen ; the others, appear¬ 
ing shaded or blended, are successively brought clearly into the line of sight 
by movements of the head. 

Operative Treatment .—Sometimes an iridectomy is performed (Tyrrel), 
which is done for the purpose of admitting light to the eye through the 
peripheral portions of the cornea. In such a case the retinal image is less 
diffused. Iridodesis, which at the same time suppresses or displaces the 
old pupil, would be preferable were it not for the inconvenience of binding 
in or enclosing the iris. The writer would prefer external iridotomy to 
iridectomy or iridodesis. Tattooing of the cornea (Grandcl6ment), which 
produces a central leucoma, seems to be no longer recommended, except as 
an adjuvant to some operative procedure to be performed afterwards. 

Numerous efforts have been made to strengthen the centre of the cornea, 
to render it more resistant, and to flatten it. (See Operations, vol. iii. p. 
824.) Von Graefe observed that a corneal cicatrix following an ulcer often 
flattened the membrane, and removed a layer comprising the anterior planes 
by passing a cataract knife at a tangent through the summit of the cornea. 
Several days later, he cauterized the wound lightly with nitrate of silver. 
After separation of the eschar, he pierced the base as it arched forward, 
and, when necessary, kept the perforation open. The result was a central 
leucoma more or less flattened. Finally, he made an iridectg 

A. Critchett and Gayet recommend the application ofV 
tery to the summit of the cornea, which it cauterizes ytiLiut always per¬ 
forating. Even if perforation should occur, it is nofC^rave accident, for 
the aqueous humor which flows out cools the >n. The effect is the 

same as that obtained by the preceding mIt is usually necessary 
afterwards to make an artificial pupil. Ewa^/ pushes cauterization so far 
as to cause perforation, which he believe^N^ssential to the production of a 
flattened cicatrix, and is without dangers' Knapp and R. Williams share 
in his opinion. 

Bader excises an elliptical nrao^bmprising the entire thickness of the 
membrane from the summit cornea, which he punctures with a von 

Graefe knife and then cu^ i\^ff with scissors. Adhesion of the iris, which 
necessitates an iridectomy^! ways results. Bowman, instead of excising an 
elliptical piece, remmlSd) a disk by means of a small trephine; in this case 
also adhesion of thQ^re was produced. Later, he excised a ring comprising 
all the tissue^O^pt the membrane of Descemet, which, bulging into the 
lacuna, he pi^rcSl in such a way as to maintain for some time, perhaps a 
month, a torneal fistula. The danger of anterior synechia was thereby les- 
sened^Ctjs evident that in all these operations rigorous antisepsis and the 
proj^nged wearing of a bandage are necessary. None of these efforts have 
tJIJtrTar led to a satisfactory result, and we may repeat to-day what Soel- 





berg Wells said in 1873, “ All these methods of treatment of conical cornea 
are still upon their trial, and nothing decisive can as yet be said as to their 
relative advantages or disadvantages.” 

Miotics, when used for a sufficient period of time, seem to act favorably 
in cases of conical cornea, the progress of which they moderate or check by 
reducing the tension in the anterior chamber. Sometimes the only benefit 
to vision derived from their employment is due to contraction in the size 
of the pupil. 

Pauas claims to have obtained satisfactory and lasting results by com¬ 
bining the employment of pilocarpine at least three or four times a day, and the 
wearing of a compress bandage for a period of from six to eighteen months 
As this treatment is not at all injurious, it is well to try it in the beginning. 
If the patient does not submit, or if the effect is unsatisfactory, cauteriza¬ 
tion with the galvano-cautery may be resorted to, or even excision after the 
method of Bader or Bowman made. The operation should be followed by 
the use of miotics and the prolonged wearing of the compress baudage. 



The cornea is so very seldom the seat of neoplasms and tumors that 
many authors deny that they ever primarily occur therein. On the other 
hand, the conjunctival limbus is often the starting-point of tumors which 
may secondarily invade the cornea to a greater or less extent. The tumors 
of the limbus, however, whether malignant or benign, <k)ngenital or ac¬ 
quired, all have one peculiarity in common, and that is t^ioslight tendency 
to invade adjacent parts, especially the cornea. They usually form more 
or less prominent projections, which adhere to tl^Qhnbus, the cornea, and 
the sclerotics by a slender pedicle that rarely ^^ps out any deep root either 
towards the interior of the eye or towan^jme cornea. While there is 
reason to believe that this vulnerabilityQrf^tSe limbus is due somewhat to 
the great number of its large lymph^jclacunse, this does not explain the 
extreme rarity of neoplasms in th^cornea, a membrane in which the 
nutritive interchanges are quitej^tive and which is constantly exposed to 
traumatisms and infections fefcuAvithout. 

It is not our purpos&^4reat here of sclero-corneal tumors. Of those 
which attack the con*eai^;clusively, epithelioma is the only well-authenti¬ 
cated and fully idenV£j*l neoplasm, and it is very rare. Under the name 
of corneal fibromC^nd corneal sarcoma other growths, which were gener¬ 
ally small in Mnme, pedunculated, and formed fundamentally of differ¬ 
ent variei^^GS conjunctival tissue, have been described. The designation 
“ fibronft&vSippears in some cases to have been applied to them incorrectly. 
Aftertoeing extirpated they have seldom reappeared. 

Epithelioma of the Cornea .—We are able to present here a well- 
Thenticated example of corneal epithelioma, which has already been pub- 
shed by W. Snellen. 




In an elderly man, who had been to the Dutch Indies, a pterygium, 
that had reappeared after being removed by operation, had given rise to an 
epithelioma, which had invaded and considerably thickened the whole of 
the cornea. (Fig. 24.) Several aggregations of cells overlapping each other 
like so many onions show that the neoplasm, which was apparently epi¬ 
thelial, was really of a cancerous nature. At a, the spot where the neo¬ 
plasm penetrates into the depth of the cornea, the surface looks as though 
it were embossed. On that side the conjunctival epithelium is slightly 
thickened, but not as far as the cul-de-sac , and the sclerotic is not invaded 
at all. 

In other words, the epithelioma, which originated in the cornea, has de¬ 
veloped almost exclusively in that membrane, and has grown only by in¬ 
crease in breadth, no prominent projection appearing on the surface. Having 
penetrated the cornea, it extends under Bowman’s membrane and the epi¬ 
thelium, which are practically intact. Worthy of notice are the thickening 
of the cornea and the plaiting of Descemet’s membrane, showing, as they 
do, that the neoplasm has involved the cornea only as far as the growth 
has extended. 

The neoplasm shows no tendency to perforate Descemet’s membrane, 
and seems to meet a serious barrier at the periphery of the cornea, for it 
spreads in every direction over it. Neither does it enter the sclerotic. It is, 
therefore, distinctly a corneal neoplasm, although it developed in another 
pathological process which migrated to the cornea before becoming cancerous. 

Steiner recently published an analogous case, although ifewiowed some 
hesitation in diagnosing it as an epithelioma. We once extirpated a small 
tumor that had developed in the apex of a pterygiuitfSy^Lt was five milli¬ 
metres long by three in breadth, and protrudedmillimetre. Com¬ 
parison would seem to show that these tumor^wre both of a cancerous 
nature. It is worthy of note that Steine^g>jWient was an old Javanese, 
and that Snellen’s case, as mentioned flfoowj/vas that of a man who had 
resided in the Dutch Indies. 

Growths diagnosed as corneal ^)uneliomata have been reported by 
Stellwag, Galezowski, Colsman, ^h^^Lreacher Collins. 

2. Corneal Sarcomata and (^mrnmata .—In a sixty-year-old man Iium- 
schewitsch found a tumor^ijhated within one millimetre of the limbus 
corner, consisting of ffBrilMy stroma thickly interspersed with fusiform 
cells and covered v^hNpthelium, to which he gave the name of primary 
sarcoma of the corn An analogous case is reported by Pagenstecher. 
Silex designate^ fibroma a projection, eight millimetres wide and four 
millimetre^to^h, covered with epithelium and containing vessels and a 
number ol^lwall cells, which had developed on an old cicatrix. Benson 
has had\i seventy-two-year-old patient with a glaucomatous eye, who at- 


4 ? 

tribM^I to traumatism a small tumor near the centre of his cornea. An 
afajWous case came under the notice of Story and Scott, but the tumor was 



Other anomalous growths which have been seen on the surface of the 
cornea by various authors can be placed in the category of sarcomata or in 
that of fibromata with still less certainty than the above. 

To sum up, of all the conjunctival tumors found on the cornea some are 
excrescences from corneal cicatrices, while others are congenital and might 
very easily be regarded as abnormally implanted dermoids. None of them 
are reported to have reappeared after being extirpated. 

3. Corneal Leprosy .—The cornea is sometimes invaded by leprosy in its 
general tuberculous form, but never, it would seem, by anaesthetic leprosy. 
The infection evidently takes place in all cases through the limbus,—that 
is, towards the conjunctiva,—for it is always on the periphery of the cornea 
(in its tissue proper) that the tubercles first make their appearance. In 
most instances the iris is invaded secondarily, next after the cornea. The 
chorioid and the retina may likewise be involved later. The leprotic focus 
on the cornea consists of agglomerations of young cells which contain Han¬ 
sen’s bacillus and some vessels. The tubercle grows soft, ulcerates, and 
exhibits a tendency to perforate the cornea; hence iritis, etc., and loss of 
the eye by atrophy may supervene. Local treatment consists preferably in 
the destruction of the nodules by thermo-cautery, followed by the usual 
antiseptic applications and the bandage. As to general treatment, notably 
the internal use of chaulmoogra oil (up to three hundred or even four 
hundred drops per day), the reader is referred to the special works treating 


(See Tumors of the Conjunctiva.) 

(See Wounds and Injuries of t^ie^>|^balL) 



Professor of Ophthalmology in the University of Pennsylvania and one of the Attending 
Surgeons to the Wills Eye Hospital. 

Fig. 1. 


The normal position of the human lens varies very much at different 
stages of development. When first formed it fills almost entirely the 
secondary optic vesicle and its posterior surface lies nearly in contact with 
the retina, while in eyes which go on to proper development the vitreous and 
its accompanying blood-vessels insert themselves between the lens and the 
retina, and at birth we find it lying in the 
anterior part of the eye, its posterior cap¬ 
sule being embedded in the fossa patellaris 
of the vitreous humor in close contact with 
the hyaloid membrane, while its anterior 
capsule is bathed by the aqueous humor 
and supported at the margin of the pupil 
by the circular fibres of the iris, which are 
separated from it only by a capillary layer 
of fluid. Near the equator it is every¬ 
where held in place by the delicate fibred 
which its suspensory ligament (the zc^f^ 
of Zinn) sends into the anterior, equato¬ 
rial, and posterior capsule (Fig. IflXrThe 
zone of Zinn is itself firmlj^^clred to 
the ciliary processes, ciliaivpvKhdies, and 
anterior part of the retina, Jvnile it sends 
a layer forward whic^dips down into the 
recesses between thaN^fnary processes and 
runs forward J:q/fc^roie the posterior sur¬ 
face of the Held in place by such 

delicate fcuiiNwhobile and yielding sur- 
ronndmg^s^he lens is normally capable of changing its curvature with 
the ^rySng tension of its elastic suspensory ligament and capsule, and of 

^ig accurately its place in the eye in spite of the very considerable 
Vol. IV.—17 257 

Insertion of suspensory ligament 
lens capsule. (Topolanski.) 




shocks imparted to it by the sudden arrest of motion in movements of the 
eye, and of transmitted shocks of the body and head in various athletic 
exercises, such as running, jumping, boxing, etc., and even at times of 
resisting considerable direct violence to the eyeball. Any decided loosen¬ 
ing of its suspensory ligament, especially if accompanied by a fluidity of 
the anterior part of the vitreous, is betrayed by a slight wabbling motion 
of the iris concomitant with the excursions of the eyes and a variation in 
the depth of the anterior chamber. While any displacement of the lens 
either forward or backward must affect the refraction of the eye and either 
lengthen or shorten its principal focal distance, still it is usually only when 
the lens becomes either slightly decentred or rotated on one of its axes that 
the displacement of the image and the astigmatism thus produced markedly 
interfere with visual acuity and cause the patient to seek medical advice. 

The lens may assume an abnormal position in the eye, either as the 
result of congenital malformation, of disease, or of external violence. In 
all such cases there is a luxation or dislocation of the lens, but most writers 
assign to the congenital displacement the name of misplaced lens (ectopia 
lentis) and speak of displacement due to other causes as luxation or dis¬ 
location of the lens, while Becker reserves the latter term for secondary 
displacement of the lens (as, for example, that due to the formation of a 
staphyloma of the cornea). 



In some rare cases of so-called total coloboma of^tl^we the develop¬ 
ment of this organ is so completely arrested that never comes 

forward to .occupy its normal position, but reiifmjrs embedded in the 
vitreous chamber attached to the intra-ocular/eSd of the optic nerve by 
the hyaloid artery and the foetal vessels aApf posterior capsule, while 
anteriorly it is attached to the indrawi/T^S^y remnants of the pupillary 
membrane. Usually, however, conge$uta^*flislocation of the lens is due to 
a faulty development of the suspei^ry ligament, the lens being pulled 
toward the point where this is stMagest and best developed, and away from 
the point where it is weakest^i entirely wanting. This faulty develop¬ 
ment or coloboma of the < ^Zinn is at times accompanied by a cor¬ 

responding coloboma oi/lyfe lens, iris, ciliary bodies, chorioid, and optic 
disk. It may, howe^erj occur without any demonstrable lack of develop¬ 
ment in these orggjjs, and is often accompanied by a flattening or notch in 
the equator of tkisjfens at the point of the most faulty development of the 
zonule. Xli^>^mch, where it exists, is readily seen with the ophthalmo¬ 
scope asJj^^&tk in the otherwise continuously curved, blackish line of the 
lens circumference, and has been described as coloboma lentis. The con- 
ge^ikSslisplacement of the lens is usually either upward and inward, up- 
juxfc; or upward and outward; rarely or never downward, the weak point 
the zonula usually corresponding to the position of the foetal slit. It is 



generally found in both eyes and in a symmetrical direction. It is often 
for years stationary, but there is a tendency as the patients become older for 
the displacement to increase. The amount of mobility of the lens varies 
very greatly. In some cases the zonula is so long as to permit of the dis¬ 
location of the lens into the anterior chamber, and this may occur while the 
capsule and zonula are both intact, as is evidenced by the fact that the 
stretched fibres of the zonula and the corresponding irregularities in the 
periphery of the lens can then be readily demonstrated with the magnifying 
glass aided by the use of oblique light. Becker has reported an interesting 
case, observed in a child of eight years of age at Arlt’s clinic, where this 
excessive mobility of the lens without rupture of the zonula was seen. 
Here, as in most cases of congenital dislocation, the lens itself was of much 
less than the normal size. When the lens falls into the anterior chamber 
it is sometimes free from all zonular attachment, although still covered by 
its capsule, the delicate fibres between the two having given way. Slight 
ectopia often passes unobserved in infancy and early childhood and it is 
only when at school that the child is found to have defective vision. Care¬ 
ful examination usually reveals an anterior chamber unequal in depth, the 
most anterior part of the lens pressing a corresponding part of the iris 
forward, while at the opposite side of the chamber the iris not receiving 
support from the lens lies at a deeper level, and both iris and lens wabble 
with the motions of the eyes. Looking at the eyes with the ophthalmo¬ 
scope, even with undilated pupil, usually confirms the diagnosis by showing 
at some part of the pupil the curved black line caused by the Reflection of 
the return light from the eye ground by the equator of the^ra. So long 
as the luxated lens still occupies the entire pupillary spacrt&fcfsymptoms are 
usually those of myopia and astigmatism, and whera-Q^mobility of the 
lens becomes slightly greater the amount of thes^HWects will vary with 
the different positions of the head and eyes. WfiWe a displaced lens only 
partially occupies the pupil and its edge eittfe^plects it or leaves any con¬ 
siderable portion free, the patient with th^imrfaed eye is much annoyed by 
double vision, the refraction through tl^jnee part of the pupil being in 
high degree hypermetropic (as in tl^^phakic eye) while that through the 
part occupied by the lens is still^^opic and astigmatic. Such cases also 
offer a most instructive opht|k$^scopic picture, and as we approach the 
eye, using the usual conca^efimiror, we see through the part of the pupil 
still occupied by the led^jJshadow moving with the mirror, and through 
the lensless part of ♦tljfl^pupil another shadow moving against the mirror, 
while with the pkftaB reflector these conditions are of course reversed. 
Where we take <^$5ndensing lens and use the inverted image to examine 
the eye-grot^d/^Ve often obtain simultaneously two images of the fundus, 
one through me lens and the other through the lensless portion of the 
pupill^v^ace. Fig. 2, taken from Streatfeild, 1 gives a view of the 

Xr -- 

Streatfeild, Royal London Ophthalmic Hospital Reports, yol. vii. p. 394. 



Fig. 2. 

Double images of eye ground seen by use of concave 
mirror and condensing lens in an eye with ectopia lends. 

double images thus obtained with a dilated pupil. This author informs us 
that “ in slight movements of the patient the retinal vessels in the same pu¬ 
pillary area seem to move in two contrary ways at once.” The lenses were 
slightly cloudy, but after a downward iridectomy with-f 1/3J V.=20/XX. 

In such conditions the lens is 
sometimes so mobile that by 
leaning forward, bending the 
head downward and rolling 
the eyes in the same direction, 
the lens will fall forward into 
the pupillary space, and thus, 
causing a temporary myopia, 
enable the patient to read 
ordinary print when the book 
is held downward and close to 
his chest. When the lens still 
occupies most of the pupil it 
is advantageous to give the eye 
a myopic correction, but where 
most of the pupil is aphakic, a hypermetropic correction (as if for a patient 
after a cataract operation) is advisable. In either case the correction so 
much aggravates the defect existing in the other part of the pupil and 
renders the retinal image received through it so diffuse and faint, that the 
patient is much less annoyed by double vision than he iswhen using the 
eye without a correcting glass. 

Ectopia of the lens is often hereditary and existe^p several members 
of one family. Dixon 1 was the first to call our^fiSition to this fact, but 
since that time numerous instances have been^e^^ted. The most interest¬ 
ing and extensive group of such cases of wW4am aware is that reported 
by Morton, 2 and refers to the same fafcwAriginally studied by Dixon. 
The family record traces this defect though five generations. The diagrams 
which he gives of six of this interes(^ series of cases are here reproduced 
(Fig. 3) and show the directionextent of displacement in various mem¬ 
bers of the family. The acuijO^ vision obtained by correcting glasses in 
each is also given, and it appears that all eyes had more or less myopic elon¬ 
gation of the axis, i as the glasses giving the best vision in the 

aphakic part of the ^yjil varied from -f 1/5 to -f-1/7 or even + 1/10. All 
the lenses havingK^P dislocated inward or inward and upward, a divergence 
of the eyes in <|lMknt vision occurred when concave glasses were used, while 
there was <<^(^rgence when convex ones were employed. The marked in¬ 
fluence i^^edity is also shown in several interesting groups of cases. 
Bitsg^h 3 reports an instance where a grandmother with ectopic lenses 



Dixon, Royal London Ophthalmic Hospital Reports, vol. i 

2 Morton, ibidem, vol. ix. p. 435. 


8 Bresgen, Centralblatt fur praktische Augenheilkunde, 1897, S. 104. 


had two daughters with the same congenital anom- Fig. 3. 

aly, and the six children of one of these daugh¬ 
ters were all similarly affected. A son, completing 
the family of three, was born with good eyes, but 
his only child (a son) had misplaced lenses. Mules 1 
relates the case of a father with ectopic lenses, 
every one of whose ten children were similarly 
affected. Tiffany 2 observed a family of nine 
children, seven of whom were affected with bilat¬ 
eral congenital displacements of the lens. The 
remaining tw T o had no trace of the defect, but 
healthy hypermetropic eyes (about 3 D.). Miles 3 
reports the case of a mother who had ectopia of 
both lenses, which subsequently fell into the 
anterior chambers, from which they were in turn 
successfully extracted. She had eight children, 
two of whom had good vision, while the remain¬ 
ing six showed marked ectopia lentis. 

Ectopia of the lens is sometimes accompanied 
by a corresponding displacement of the pupil 
(corectopia). An instance is related by Alexan¬ 
der 4 in 1874, and later Jones 5 gives a case of 
symmetrical dislocation of the lens and pupil in 
both eyes of an individual whose brother pre¬ 
sented only corectopia, the lenses being in normal 

E. Williams 6 describes corectopia with ectopia 
in both eyes of a brother and sister. SauvineauJ 
reports a case of corectopia with dislocation 
the lens in both eyes of a patient with hen 
syphilis and atrophic patches in the chor^i^md 
Schaumberg one of corectopia with cong^njml dis¬ 
placement of a notched lens, while Sr Duyse 
gives two cases of double corectmija^n which the 
pupils were displaced outw^oplhe cataractous 
and ectopic lenses being inward. Breitbarth, Pufahl, Frickhoeffer, 

Theobald, Wicherkiewic^a|d Lindner have all recorded cases of corectopia 

Six cases of ectopia lentis occur¬ 
ring in one family. (Morton.) 

iew, 1883, p. 84. 
sactions of the Ophthalmological Section of the American Medi- 

1 Mules, Ophthal 

2 Tiffany, F. B 
cal Association.^^ 

3 Miles, of Ophthalmology and Otology, July, 1896, p 642. 

4 Alexai^er^ Klinische Monatsblatter fur Augenheilkunde, 1874, S. 60. 

5 J^p^^ublin Journal of Medical Science, 1879. 

Oh\ffilliams, Transactions of the American Ophthalmological Society, 1875, p. 291 
rtkuvineau, Annales d’Oculistique, July, 1896, p. 55. 
en r an Duyse, Archives d’Ophtalmologie, December, 1895. 



with ectopia lentis. Damianos 1 has found in literature fifty cases of corec- 
topia with ectopia lentis and records two new cases from Fuck’s clinic. 
Ectopia lentis may also occur with congenital aniridia, and cases are cited 
by Gouvea, Klein, and Rindfleisch. According to D’Oench 2 * ectopia lentis 
occurs once in about five thousand cases of eye disease, while in eighty 
per cent, of the cases the lens remains clear. 


The so-called spontaneous luxation of the lens is always really a secondary 
process, consequent upon pathological changes which have previously oc¬ 
curred within the eyeball. These are sometimes so slight and chronic that 
the displacement of the lens affords the first evidence of their existence, 
while at other times they follow such marked ocular lesions as anterior 
synechia, staphyloma of the cornea, intercalary staphyloma, etc. Where 
the displacement is so slight that the lens still remains in partial contact 
with the fossa patellaris, it is usual to speak of a subluxation, but, when the 
lens vacates the pupillary space and comes to lie either in the vitreous or in 
the anterior chamber, the luxation is said to be complete. Luxation of the 
lens may occur either while that organ is perfectly transparent or after it 
has become cataractous. If it be quite clear at the time of its displacement 
it usually becomes cloudy after a prolonged sojourn either in the vitreous 
or in the anterior chamber, and in either case, even when enclosed in its. 
capsule, it loses weight and becomes smaller. Even in traumatic disloca¬ 
tion, the lens may retain its transparency for several weekend in luxation 
from disease, although it fall into the anterior chajrogr, nt may remain 
without marked opacity for a long time. WeckeyOwfentions an instance 
where the dislocated lens maintained its transjmmncy in the vitreous for 
eight years, and Recordon 4 5 one where it r^gulied transparent for four 
years. C. Jaeger 6 claims to have seen itjm&jmi transparent for a period of 
thirty years. > 

Any such change of place in th&4p^s necessarily implies either a fore¬ 
going relaxation or a rupture of the sta-spensory ligament, and this is usually 
preceded by a breaking down and fluidity of the anterior portion of the 
vitreous. Both these chmigK d?e in all probability due to pathological 
alterations in the blood-v^ws of the ciliary processes and consequent alter¬ 
ation in the nutritiorfT qfiAhe suspensory ligament and vitreous; but our 
clinical knowledge mS-tne facts has at present far outreached our limited 
information as tb^5underlying pathological processes. Becker 6 has called 
our attentiom^Ohe fact that in case of opaque lenses the formation of cap- 

1 N., Beitrage fur Augenheilkunde, 1897, Heft xxix. S. 8. 

2 iVOeSeb, Archives of Oph that mol ogy, vol. x. p. 93. 

/JmWecker et Landolt, Traite complet d’Ophthalmologie, tome ii. p. 824. 

v >4j£e(fordon, Annales d’Oculistique, 1852, p. 233. 

5 C. Jaeger, Dissertatio inauguralis, 1823. 

6 Becker, Graefe und Saemisch, Handbuch der gesammten Augcnheilk., Bd. v. S. 290. 



sular cataract may be the exciting cause of the rupture of the zone of Zinn. 
The newly-formed spindle-cells and effused material of capsular cataract 
are always on the inside of the capsule, and, as they become older, firmer, 
and more organized, go on to contract, pulling always in the direction of the 
chord of an arc, and cause the folding of the capsule which we so often find 
in such cases, and at times by a continued pull in this same direction cause 
a separation of the fibres of the zonula from the capsule so that the cata- 
ractous lens, still covered by its capsule, but absolutely free from its zonular 
attachments, lies loose in the fossa patellaris of the vitreous. Beer, Wen¬ 
zel, and others of the older writers have already called our attention to this 
fact, stating that cataractous lenses on attempts at extraction will sometimes 
escape from the eye, still enclosed in their entire capsule and without loss of 
vitreous, and every experienced eye-surgeon has doubtless occasionally en¬ 
countered a similar state of affairs when operating for the extraction of 
over-ripe cataracts. The partial displacement of the lens from the pupillary 
space in any case of subluxation tends constantly to increase. There is a 
continuous drag from the yet intact or comparatively sound portions of the 
zonula, and the greater specific gravity of the lens causes it to move with 
every movement of the eye, thus tending further to break down and soften 
the vitreous, so that the lens eventually quits the pupillary space and in 
time usually subsides in the partially softened vitreous humor. In all cases 
of spontaneous dislocation, therefore, the lens is eventually dislocated down¬ 
ward, and when in cases of long standing we find it dislocated upward we 
may be sure that the luxation has been either congenital Dr traumatic. 
How easily partially dislocated lenses may at times be entii^tAdislodged is 
shown by the case reported by Pufahl, 1 where a partially/jjpocated lens had 
drawn the zonula across the pupil and a single stroko*Q\me needle allowed 
it to sink into the vitreous, the vision rising proimtfl^rom counting fingers 
at two feet to ability to read Jaeger III. 

Siebold 2 (senior) gives a most instructiv^om^f spontaneous dislocation 
of an opaque lens. When he first saw $he patient the lens was wabbling 
with the motions of the eye, and he fed an operation for depression. 
A year later the patient had a clear .© mobile pupil, and exhibited herself 
with joy as cured without operati^^ In 1831 Desgranges 3 relates a case 
of a peasant, fifty-six years where the cataract had existed for nine 

years, when, while thrasj^ii^yhn a barn, he perceived a sort of shaking in 
his eye and could once m^rejsee with it. Fischer, in his “ Lehrbuch” (1846), 
appears to have seeji @^ 7 eral such cases, and says, “ there are cases in which 
the cataract sponten^eusly disappears, either by sinking in the vitreous or 
by accidental iramg of the capsule,” and details a case where the sinking 
happened the patient was using a solution of lapis divinus with 

Sydenhan^s raudanum, “ who subsequently kept the precious recipe as if 

agel, Jahresb. iiber die Leist. und Fort, im Geb. der Oph., 1875, S. 410. 
t>old, Himly und Schmidt, Bibliothek, 1802, S. 187. 

2 0t>< 

isgranges, Compte-rendu des travaux de la Societe de med. de Lyon, 1881, p. 54. 



it were gold, and recommended it to all blind people.” Sichel, 1 however, 
was the first to give us an elaborate dissertation on spontaneous sinking of 
the lens, and in some of the eight cases reported by him the lenses were 
entirely cataractous, in some partially so, and in others entirely clear. 
One partial dislocation in a man of eighty was followed by glaucoma, and 
in one case the dislocation occurred at the age of eighteen in an eye with 
congenital cataract. His first case was so accurately observed, and fol¬ 
lowed over so long a period of years, that an abstract of it is instructive. 
A clerk in the custom-house, aged fifty, always myopic, found his sight 
beginning to fail. He had previously worn —1/4 and — 1/3J. The right 
eye, after becoming so dim as to be useless to him, subsequently presented 
a narrow field in which he could see at a distance, and in which the vision 
was improved by a convex glass. This occurred when the left eye had in 
turn become so dim that he could scarcely see to work, even with his 
nose almost touching the paper. Still later a similar change occurred in 
the left eye, and when looking downward a cloud came over his field from 
above, while when looking up he could see an elliptical disk. Finally, in 
both eyes these disks entirely disappeared, the opaque lenses having sunk 
into the vitreous and becoming fixed so that motions of the head did 
not displace them. The patient six years later was still, by means of 
cataract glasses, working comfortably at his business as book-keeper. The 
process of spontaneous sinking took about five years to complete. It 
may, however, occupy a much shorter period of time. Recordon (1. c.) 
observed a patient of seventy years of age who, while waiting in the hos¬ 
pital for a cataract operation, was kept abed by rheum^sir^ and observed 
one day that while in the recumbent position he coutflhsee the upper part 
of the window-frame, but that this disappearedhis vision clouded 
when he sat up in bed. In “ about eight days^we lens had entirely dis¬ 
appeared in the vitreous. 

The immediate results of such spontaneous luxation when the lens has 
been cataractous are, of course, a source ofmucli satisfaction to the patient. 
Many such cases are on record, b^in most instances the intra-ocular 
changes which have produced tlj^^uxation continue, the vitreous becomes 
fluid, and the lens, if it rests (|iKthe vitreous, not only by its gravity, in 
the motions of the eye, co^KStes further to break down its structure, but, 
acting on the chorioiTa^K^niary processes as a foreign body, gives rise at 
times to atrophic profcs&s in these organs, or at others produces attacks of 
glaucoma. The* Jgfcter termination is more frequent where the partially 
dislocated lens/pN§ses on the pupillary margin of the iris. The clinical 
results of th^sprocesses are well illustrated by the following cases related 
by Arlt^^y \y Theobald. 3 The former author saw in a boy of thirteen 

L^sael, Spon. Dislocation und Depression der Linse, Zeitschrift fur die gesammte 
Medl^iJi, T5d. xxx., Hamburg, 1836. 

Arlt, Krankheiten des Auges, Bd. ii. S. 273. 

3 Theobald, Transactions of the American Ophthalmological Society, 1892. 



years a dislocation of the transparent lenses of both eyes into the anterior 
chambers. The lens of the right eye was extracted with slight loss of 
vitreous. Three years later the operated eye remained useful, while its 
fellow had lost all light-perception. The lens of the unoperated eye had 
spontaneously fallen back into the vitreous, causing occasional attacks of 
pain, while a conical staphyloma of the cornea had formed, so prominent 
as almost to prevent closure of the lids over it. A younger sister of this 
boy had similar dislocations of transparent lenses into the anterior chambers. 
The eyes, left to themselves, became glaucomatous and sightless, with 
atrophy of the iris and dilatation of the pupil. The lenses, which had 
become opaque, had fallen back into the posterior chamber. In Theobald’s 
case a lad of eighteen years had for ten years been able to shake a dislo¬ 
cated but transparent lens into the anterior chamber, and preferred this 
adjustment of‘the eye to any cataract glass which could be supplied him. 
The lens finally commenced to lose transparency, and later the capsule 
ruptured, this being accompanied by marked inflammatory action. Lens 
fragments could be seen floating in the vitreous. A year after this occur¬ 
rence one of the fragments fell into the anterior chamber and excited in¬ 
flammation. The eye once more became quiet when, after artificial dilata¬ 
tion of the pupil, the fragment was again shaken back into the vitreous. 

Chisholm 1 reports two interesting cases of spontaneous dislocation, in 
one of which the optic nerve became atrophic in a few months, while in 
the other vision one year after the accident was still good. 


Temporary traumatic subluxation of the lens maa*Jj£Aimes be produced 
by injuries limited to its suspensory ligament,—asJi^Vell shown in the case 
of Aub, where the eye received a severe blow fr&m<a bird-shot, which, how¬ 
ever, did not puncture it, but was found lyin^m the conjunctival sac. On 
the fourth day after the accident there>w®j£/ciliary injection, a contracted 
pupil, and a slight effusion of blood ipt^the anterior chamber. Dilatation 


t me 

of the pupil by atropia showed that me lens was transparent, but that it 
was tilted forward at its uppe&^wfcer part. There was metamorphopsia, 
and a walking-stick held di^g^aH^ appeared club-shaped at its upper part 
while it had its normal apu&^ince when held in a direction at right angles. 
On the thirteenth daj/TljNftns and iris had returned to their normal posi¬ 
tion, and, although tjiehrwas slight myopia, nevertheless vision equalled 
20/XXX. PerforaAS^ wounds of the eyeball may at times be limited to the 
suspensory liga^pjt and its immediate surroundings, so that a slight change 
in the for^K^J position of the lens may be the only result of the injury. 
Thus, BeclS^^ details an injury to a boy’s eye by a fragment of cap, causing 
a t hr^^l limetre wound in the sclerotic just below and to the inside of 



sholm, American Journal of Ophthalmology, April, 1893. 

►ecker, Graefe und Saemisch, Handbuch der gesammten Augenheilk., Bd. v. S. 293. 



the cornea, where after excising the prolapsed iris useful vision returned, 

although through the coloboma thus produced a well-marked flattening of 

the equator of the lens could be seen at the part where the suspensory 
ligament had been injured. Five years afterwards the eye was in the same 
condition, although the piece of cap still remained in the eyeball. Any 
injury to the eyeball which presses on the zonula or the lens itself may 
cause either partial luxation or by interference with the zonula produce 
unequal curvature of the lens. Berlin 1 reports twenty-one cases of astig¬ 
matism after injury which he attributes to hemorrhages in the ciliary body. 
Schiotz gives a case of lenticular astigmatism produced by the pressure of 
a cyst of the iris, which disappeared after the removal of the cyst. Injuries 
limited to some portion of the zonula are, however, exceptional, but it is 
not unusual to have complete luxation of the lens either into the vitreous 
or into the anterior chamber as a result of blows upon the eyeball or its 
vicinity, and the sequelae are likely to be similar to those following spon¬ 
taneous dislocation into like positions. Severe blows on the eye often cause 
a rupture of the ball at the side opposite to the blow, with dislocation of 
the lens, sometimes causing a complete extrusion from the eyeball; at others 
the elastic conjunctiva escapes rupture and the lens is driven between the 
conjunctiva and the sclerotic. 


In some rare instances the escape is not complete, and the lens lies be¬ 
tween the lips of the wound, which mav 

Lederle’s case^^arge irido-dialysis permitted a good view of the part of 
the lens lyin^yviftfin the eyeball. 


previously mentioned, a blow may at times burst the retina, chorioid, 
erotic and drive the lens under the conjunctiva, which by its greater 

1 Berlin, Bericht der Ophthalmologischen Gesellschaft Heidelberg, 1877. 



Subconjunctivaj3tetecation of the lens, with subsequent cataractous degeneration. 

(Photographed by Dr. James Wallace.) 



elasticity may itself escape rupture. Owing to the protection afforded to 
the eye by the frontal bone from all blows coming from above, ruptures of 
the eyeball usually occur at the upper part, being produced by blows com¬ 
ing from below, but Lawson 1 pictures an exceptional case where the rup¬ 
ture of the eyeball occurred at the lower margin of the cornea while the 
lens lay under the conjunctiva to the inner side of the rent and slightly 
above it. Treacher Collins 2 also relates a case where the lens was dislocated 
under the conjunctiva downward and outward. The eye healed and with 
-f 11 D. V. = 20/C. The case was seen eighteen years later, and the eye had 
not given any trouble. The lens could still be seen as a slightly raised 
yellow patch at the lower outer part of the globe. Higgins has reported a 
case of subconjunctival luxation of a cataractous lens, caused by the blow 
of a fist, where the final visual acuity exceeded that of the fellow-eye which 
had been successfully operated on in the usual manner. Such injuries, how¬ 
ever, by no means always result harmlessly even when vision is retained. 
Jacobs describes a case where the eyeball was ruptured by the blow of a 
finger, the lens driven under the conjunctiva, and the iris was either torn 
out or turned back so completely as to be invisible. Inflammation gradu¬ 
ally subsided, but seven weeks later sympathetic iritis developed in the fel¬ 
low eye and extinguished the sight. The exciting eye with a proper dia¬ 
phragm and a cataract glass retained a moderate amount of vision. 

The accompanying figures are from a case of the author where the sub¬ 
conjunctival dislocation was upward and inward and had been produced by 
the patient falling against the edge of a stove. The rupture of the sclera 
was firmly cicatrized, the cicatrix enclosing pigment fra^T^ie entangled 
ciliary processes and chorioid. The lens itself was So* Jularly globular 
in shape, still enclosed in its capsule, the epithelmjNof which, although 
somewhat atrophic, was distinely to be follower 10 ^continuous layer over 

iselves were everywhere 
The cataractous changes 

were more marked near the capsule. %.5 gives a moderately magnified 

lowe<; 10 

a considerable part of it. The lens-fibres ^cWtais 
commencing to undergo molecular degen^aupK - 

view of the entire region involved, shying the pigmented cicatrix in the 
sclerotic with the lens in its capsffi^ and lying beneath the conjunctiva. 
The capsule is adherent to the seQy^tic and in places also to the conjunctiva. 
The latter membrane at one^mA lias undergone considerable inflammatory 
thickening. The lens i is0> fwhere undergoing cataractous degeneration. 

Fig. 6 shows the f^mi^ preparation, under a higher magnifying power, 
at a point where tji^apsule is adherent to the conjunctiva. The capsular 
epithelium can WyJistinctly seen in a somewhat shrunken and atrophic 
condition. TI^t^is marked molecular degeneration of the lens-fibres with 
numeroue-shaped chinks between them which are for the most part 
filled with granular material. Further from the capsule is to be seen a 



Lawson, Injuries of the Eye, Orbit, and Eyelids, 1867, p. 202. 

Treacher Collins, Koyal London Ophthalmic Hospital Reports, vol. xii. p. 




band of degenerating lens-fibres with spindle-shaped masses of material 
exhibiting transverse markings, while still farther in the periphery lie 
sharply-outlined round cavities in the lens-fibres, filled with granular debris. 
Alt has also given us an interesting microscopic examination of such a case. 
The capsule, which was ruptured at the equator, was thickened and adherent 
to the conjunctiva, no normal capsular cells remaining. It was covered on 
the outside by a firm spindle-celled tissue with the remnants of blood-ves¬ 
sels. “ There was granular clouding of the lens-fibres, with Morgagnian 
fluid and giant cells between the fibres.” In a case of Riegel 1 there was 
firm vascular tissue binding the intact capsule to the conjunctiva, and a 
newly-formed epithelium lining the posterior inner surface of the capsule. 
Falchi 2 reports an instance where there was rupture of the capsule with 
marked proliferation of connective tissue within it. One of the most curi¬ 
ous cases on record is that related by J. C. Wordsworth 3 where in conse¬ 
quence of a kick of a horse there was a dislocation of both lenses under 
the conjunctiva. A lens thus dislocated under the conjunctiva may for a 
long time remain visible as a more or less globular body, but usually di¬ 
minishes in size by absorption, a process which takes place more readily 
when there has been a rupture of the capsule. Sometimes the dislocated 
lens undergoes degeneration and calcareous infiltration. (Arlt, Mitvalsky.) 
The lens is usually dislocated in its capsule, but it by no means follows that 
the capsule is everywhere intact, and Alt 4 5 and Sachs 6 have each demonstrated 
anatomically rents in such capsules. Mitvalsky, 6 who has reported thirteen 
cases of subconjunctival luxation, found that in one case had the cap¬ 
sule remained behind in the eye. In some cases he foifcn^proliferation of 
the capsular cells and a gelatiniform degeneration cortical fibres. 


In rare instances where the rupture o#*"frl2p globe takes jilace at or near 
the equator, the dislocated lens may lodger Tenon’s capsule (Wadsworth, 7 
Montagnon, 8 Mueller, 9 and SchlodtrasiSa). 10 Careful sections in Schlodt- 
mann’s case showed that the lens \ras oislocated in its capsule, that the sub- 
capsular epithelium was in goocWfendition, that the lens-tissue was under¬ 
going granular degeneratkm^l5K*)reaking down into albuminous clumps. 
There was a delicate web £^Wly-formed connective tissue between the pos- 

1 Riegel, Archiv furC^jen- unci Ohronheilkunde, 1877, Bd. vi. S. 8. 

2 Falchi, NageJ, |Jjhresbericht uber die Leistungen und Fortschritte im Gebiete der 

Ophthalmologie, 367. 

3 Wordswm^A^oyal London Ophthalmic Hospital Reports, 1882, vol. x. p. 204. 

4 Alt, ^u^ra^s of Ophthalmology, 1877. 

5 Sadi^V^Schiv fur Augenheilkunde, 1879, Bd. xx. S. 367. 

6 Mitwflsky, Archives d’Ophtalmologie, 1897, p. 348. 

^J^Oadsworth, 0. F., Transactions of the American Ophthal. Society, 1885, p. 144. 

v %AL?ni 

tlcfntagnon, Archives d’Ophtalmologie, 1877, p 204 
9 Mueller, Ruptur der Corneoscleral Kapsel, 1895, S. 18. 
j 10 Schlodtmann, Archiv fur Ophthalmologie, xliv., 1, 127. 



terior surface of the leus and the sclerotic, which was much more devel¬ 
oped at either extremity of the equatorial region of the lens. 


Dislocation into the vitreous is the most common form of traumatic 
displacement, and in it, as in congenital and spontaneous luxation, the lens 
may remain transparent for some time in its new position, although it 
eventually loses weight, becomes smaller and more or less opaque. It may 
cause little disturbance in its new position beyond slight local atrophy of 
the chorioid and retina, or it may cause a serous chorioiditis, or, if pressing 
on the iris or ciliary processes, an attack of glaucoma. In time the vitreous 
breaks down more and more, and consequently the dislocated lens is apt to 
move about in the eye with various motions of the body and eyes, and at 
times when the patient bends forward to fall into the anterior chamber. 
Traumatic dislocation is usually monocular, but may at times affect both 
eyes, as in a case related by Lorch, where, after a fall on the back of the 
head, dislocation of both lenses followed. Where the lenses have been 
previously cataractous the immediate result of a traumatic luxation is often 
satisfactory. Janin, 1 for example, relates two cases where, in consequence 
of a fall, the cataractous lenses were dislocated into the vitreous, and in 
one of them both lenses were simultaneously displaced. Lawford 2 also 
gives the history of a case where, after three years of loss of sight from 
cataract, the opaque lens was luxated in a fit of coughing. The vision 
remained fair for twelve years, and then followed an attaak of pain and 
tension on account of which the eye was enucleated. Th^lsns was found 
to be shrunken and lying on the retina near the orag^Wua, with a small 
patch of chorioidal atrophy adjacent to it. The angl^ 
of the anterior chamber was not obliterated, ancFtpre 
was an infiltration of small, deeply-stainingsSSens 
around Schlemm’s canal. As an inst^?c?y§f the 
curious lesions which at times accompostraumatic 
dislocation of the lens may be cited W* se of Net- 
tleship where, when the patient laydown, the opaque 
lens, which was usually in tlrtKSnterior chamber, 
slipped up into a pouch betw^^me sclerotic and the 
outer surface of the iris arid ciliary body. The lens 
was extracted with sjtfgh^loss of vitreous, but four 
months later the poucliStill remained patulous. (Fig. 7.) Where the luxa¬ 
tion is originall^^^^ the anterior chamber, or where, after a sojourn in 
ens slips into the anterior chamber and becomes fastened 
we can observe a transparent body in contact with the 
* space of three or four millimetres, which gradually becomes 

1 Memoires anat, physiol., et physiques sur Toeil et sur les maladies qui 

ajfccteiu ce 

Fig. 7. 


Dislocation of lens be¬ 
tween the sclerotic and the 
outer surface of the iris and 
ciliary body. (Nettleship). 


> cet organe, Lyon et Paris, 1772. 

1 Lawford, The Royal London Ophthalmic Hospital Reports, vol. xi. p. 327. 



opaque, the cornea over it also becoming cloudy; and these symptoms are 
accompanied with considerable ciliary injection and watering of the eye. 
If not treated energetically, the cornea may either become staphylomatous 
or slough, and in the latter case the lens with the vitreous humor may be 
spontaneously evacuated. Graefe 1 relates an interesting case of dislocation 
into the vitreous, caused by the blow of a whip lash, where the transparent 
lens finally settled into the anterior chamber so firmly that no shaking of 
the head would dislodge it. After a few months the lens clouded and the 
eye became irritable. After the use of cold compresses, Graefe tried a 
moderate discission. Fourteen days later there was a mass of exudation 
around the lens and opacity of the overlying cornea, although it was still 
smooth and covered with epithelium. On the following day the cornea 
sloughed, and the lens was spontaneously evacuated into the conjunctival 
sac through a three-millimetre opening in the cornea. 

Prognosis in traumatic dislocation of the lens, whether complete or 
partial, is always serious. The injury is usually accompanied by so much 
hemorrhage into the interior of the globe and so much subsequent plastic 
inflammation and contraction as to cause eventually total loss of sight and 
shrinking of the eyeball. In rare instances, as in some of those above 
referred to, some useful sight is maintained, and in these cases vision is of 
course much improved by suitable convex glasses. 


The treatment of luxation of the lens will depend ujd&ii the position 
of the lens in the eye, the amount of injury or disease of tBe other struc¬ 
tures of that organ, the degree of mobility which the possesses, and on 
its transparency or opacity. Usually in congenit^vhxation it is best to 
content ourselves with a correction of the refii^on, being careful to do 
this with undilated pupil and with the hca<ffjmthe position in which the 
patient is likely to hold it during his wefrk.many cases where glasses 
do not afford the desired relief an irid^^sis would seem to offer the typical 
measure of operative amelioration, se^^ing a small and mobile pupil oppo¬ 
site to the centre of the lens, bijt|0p occasional occurrence of cyclitis after 
this operation usually deters u^^m employing it, and a small iridectomy, 
confined if possible to tl^ sphincter of the iris, will at times be the best 
remedy, even if it do «>©> afford as good a primary result as iridodesis. 
In these cases modeii^e^and careful discissions, taking care if possible to 
avoid wounding ♦tl^JWitreous, will often cause a sufficient absorption of the 
dislocated lens^^Teave a clear pupil, and thus enable us to obtain good 
vision witl> sTsuitable glass. Where the lens is quite loose in the vitreous 
humor, ^ehkwhere there is fair vision, it is perhaps best to operate for its 
removal fk)m the eye, inasmuch as the probabilities of the occurrence of 
glaiupun^ or serous chorioiditis or of breaking down of the vitreous and 

1 Graefe, Archiv fur Ophthalmologie, i., 1, S. 338, 344. 



i ' 

permanent lodgement in the anterior chamber become greater than those of 
undue loss of vitreous or of the awakeniug of inflammatory processes in a 
diseased eyeball by an operation. There will usually be loss of vitreous, 
but in most instances, by using a wire loop as traction instrument and gently 
pushing back the iris with it, the mass of vitreous which comes forward 
will carry the lens into the grasp of the instrument, provided it be per¬ 
fectly free from all zonular attachments. If, however, there be any rem¬ 
nant of the zonule holding on to it, it will be still further displaced in the 
vitreous, and the portions of that jelly-like mass which come forward will 
press it backward into the eyeball. A realization of this state of affairs 
has made many operators try to bring the lens into the anterior or posterior 
chamber before attempting to extract it, and to prevent its escape into the 
vitreous during operation it has been proposed to operate on the patient in 
the prone position, he leaning forward over a table (Noyes), or to secure the 
lens in its position by inserting a bident behind it (C. R. Agnew), entering it 
into the ciliary body of one side and bringing it out in a corresponding 
position on the other side. The author is inclined to fear the bident, on 
account of the necessary wounds of the ciliary region, and believes that in 
the sitting posture, the patient leaning slightly forward, the manoeuvre 
previously described will enable us usually to secure the evacuation of the 
lens. Unfortunately, owing to the increased dangers attending the adminis¬ 
tration of an anaesthetic in a sitting posture, and the deleterious effects of 
any struggling of the patient during its administration in displacing the 
lens, we usually have to forego anaesthesia, which, howevek if pushed to 
absolute unconsciousness reduces the likelihood of loss ^f^JVeous, except 
possibly in cases where there is severe vomiting duriit^rie recovery from 
its effects. Where the lens is firmly and perman^ff^y lodged in the an¬ 
terior chamber there can be no doubt of the j )ility of its extraction. 
This is best done by a small downward flap^fMfle just inside the limbus 
with a Graefe’s knife. We must remei/bea >iowever, that it may have 
become adherent to the cornea, and Ma^hner reports a case where it had to 
be scraped away from the cornea wii(^a spoon. The eye healed with a 
permanent and vascular opacity e cornea. 

In subconjunctival luxatiorjQ^ the eye becomes quiet with any degree 
of vision it is usually best^AOow the lens to remain in position. Where 
there are recurrent atfimk^ppain and cyclitis the eye should be enucleated. 
When we attempt to remove the lens it is well to wait until the sclerotic is 
firmly cicatrized,*agLto make the incision in the conjunctiva at the margin 
of the lens mosfcv^tant from the rupture in the sclerotic, to avoid any 
chance of oil^N^staphyloma following the operation. Lawson 1 relates a 
case of R^^^n’s where the removal of the subconjunctivally dislocated lens 
ten day^ after the injury was followed by the formation of a ciliary staphy- 
position of the rent in the sclerotic; while Harlan 2 observed a 

, 1. c., p. 104. 

Transactions of the American Ophthalmologioal Society, 1885, vol. iv. p. 140. 



similar occurrence ensuing in removal of the lens five weeks after the injury. 
The same author observed a case where the lens remained for three years 
under the conjunctiva while the patient still had useful vision in the eye. 




Morgagni, V. Walther, and Arnemann are all cited as giving examples 
of absence of the lens. This defect probably never occurs except either as 
the result of an arrest of development at an early stage of foetal life, or 
as the consequence of disease. The cases recorded by Seiler and by v. 
Ammon as occurring in microphthalmic eyes appear to belong to the former 
category. Dunn 1 has published an interesting case of entire absence of the 
lens. There was a central cord in the vitreous corresponding to the position 
of the hyaloid artery. The cornea was unusually globose, but Dr. Dunn 
informs me that it presented no traces of scar or cicatrix of any kind. 


The normal adult lens is a biconvex body more curved at its posterior 
than its anterior surface, and measures on an average 9.5 mm. in its equato¬ 
rial diameter, 4 mm. in its antero-posterior axis, with a radius of curvature 
of 8.2 mm. for its anterior and of 6 mm. for its posterior surface. 2 There 
is in healthy eyes some variation in measurement, but usually the size of 
the lens corresponds to that of the cornea and of the cttfflry circle, being 
larger where these are large and smaller where they aJ^mall. The space 
between the equator of the lens and the ciliaij^processes in the vast 
majority of cases remains about the same, the dkra^ter of the circle formed 
by the ciliary processes being usually aboutJWm. Slight defects in the 
distribution or in the patulousness of tire^N^al blood-vessels, however, at 
times interfere with the developmenkoiViM lens, and we find lenses which 
are small in comparison with the dr&Weter of the ciliary circle of the eye 
from which they are taken. 


Where abnormally smaj^etfses exist there may be in consequence of 
similar arrests of development a relaxed suspensory ligament, or when, 
owing to disease olfth^ye, the connection between the zone of Zinn and 
the capsule is ^weakened or dissolved, the small lens, on any sudden 
arrest of motioaa^r the eye or shock to the eyeball, readily prolapses into 
the anteri( 4 )r^i^»nber, where it appears as a small, highly refractive crystal¬ 
line disJ^S^h is frequently by some similar process shaken back again into 
the vhrajts chamber, or drawn there by gravity when, the pupil being 


. Tti 

Archives of Ophthalmology, January, 1896, p. 112. 

These dimensions are from Henle’s measurements: the radius of curvature is from 

►VbTv. Jaeger. 



fairly large, the patient assumes the recumbent position. Such lenses, how¬ 
ever, as was shown in the previous section, may remain in their abnormal 
position for a long time, retaining their transparency for varying periods, 
but usually becoming cloudy and causing inflammatory opacity and softening 
of the cornea. Hartridge 1 gives an interesting account of such small but 
well-formed and transparent lenses existing in both eyes of a brother and 
sister. The eyes were highly myopic, and when the pupil was dilated by 
atropia and examined with the ophthalmoscope a considerable space was 
seen to intervene between the pupillary margin of the iris and the periphery 
of the lens. Mitvalsky also relates two such cases. In one of these the 
horizontal diameter of the cornea measured 12 mm., while after extraction 
the partially opaque lens measured only 7 mm. equatorially, by 4.5 mm. in 
the antero-posterior diameter. Such microphakic lenses are usually fairly 
well shaped, although perhaps more globular than usual. 


In such instances where the pupil is dilated with a mydriatic the oph¬ 
thalmoscope shows a notch in the equator of the lens, usually so directed as 
to look downward, downward and inward, or downward and outward. 
The coloboma may vary in degree from a slight flattening of the convex 
edge of the lens to a deep concavity. Its edges are at times serrated and in 
rare instances we find two such indentations in the periphery. The equa¬ 
torial notch probably always corresponds to 
some accompanying malformation in the zone of 
Zinn. At times it is accompanied with coloboma 
of the iris and chorioid, and it then corresponds 
in general direction with these defects. Notches 
are usually at the periphery of the lens, but tj 
accompanying cut from Becker 2 shows tb 
may be confined to the posterior surf^e\£^:he 
lens. (Fig. 8.) The figure representeS^section 
of the lens of a new-born child suffering from 
congenital syphilis, with a horseshoe¬ 

shaped groove on its surfime0^4a)e opening of 
the horseshoe was directj^iNfmvnward and the 
lens measured 7 mmyfri ^qiiatorial diameter and 4.25 mm. in sagittal. In 
this case there was nKdefect in the zone of Zinn nor any other appreciable 
malformation ofiifif)eye. 

A colobomQr the lens may be accompanied with an upward disloca¬ 
tion, withAijGrcesponding defect in the zone of Zinn, as is well shown in 
the figu*^#Icen from a case reported by Gunn. 3 (Fig. 9.) 

Horseshoe-shaped notch in 
the posterior surface of the lens. 


artridge, Transactions of the Ophthalmological Society of the United Kingdom, 
p. 419. 

2 0. Becker, Atlas der pathologische Topographie des Auges, Tab. xii. Fig. 3. 

3 Gunn, Transactions of the Ophthal. Society of the United Kingdom, vol. ix. p. 166. 
Vol. IV.—18 



Fig. 10 depicts an interesting case of Christen. 1 In the right eve the 
iris was tremulous, and its tissue partly atrophic, although the pupil re- 

Fig. 9. 

Ectopia of both lenses, with coloboma of each lens and of the zone of Zinn. (Gunn,) 

acted promptly to light. The lens was perfectly transparent, but partially 
dislocated inward and upward. The outer lower edge was flattened, and 

Fig. 10. 

Right eye. Left eye. 

Coloboma of right and left lens. (Christen.) 4 

from it three threads of tissue extended outward towam^thfe ciliary body. 
The left eye, also represented in the figure, in addiwal to a coloboma of 

the iris upw^rch and outward, showed 
Fig. 11. a flattene$w*@riphery of the lens at this 

poinirCSfle zonula could not be demon- 
siyatVd-^n the coloboma. Dunn also 
*rts an instance of notched lens 
(h ectopia upward and inward. The 
diameters of the cornea were every¬ 
where from one to two millimetres less 
than those of the well-formed fellow- 
eye. An interesting case is recorded 
by Baas 2 where the lens was kidney¬ 
shaped, the hilus being almost directly 
inward, and projecting into it was a 
coloboma mward. pj U g 0 f re t a ined foetal iris tissue which 

had apparently prevented a proper de- 
it of the lens in this direction. There may be a double notch in 


1 Christen, Archives of Ophthalmology, June, 1896, p. 30. 

2 Baas, Klinische Monatsblatter fur Augenheilkunde, 1893, S. 297. 



the lens, as in the cases recorded by Schiess-Gemuseus 1 and by Meyer. 2 
In the latter case there were two distinct notches, one in the lower nasal 
and one in the lower temporal margin of the lens, of irregularly triangular 
form, whose apices readied about half-way between the equator and the 
centre of the lens. The intervening sector of lens tissue extended out to 
the normal position of the equator. The rest of the lens was normal in 
shape. The eye was myopic—a myopia probably due to the lens, — 2D. 
giving V. = 1/6 W/hen looking through the lens, while + 10 D. with dilated 
pupil, when the patient looked through the coloboma, gave equal acuity of 
vision. There was no coloboma of the iris or chorioid. 

Coloboma of the lens is not necessarily connected with myopic refraction. 
Bowman and Heyl 3 each observed it in a hypermetropic and Gruening 4 
in an emmetropic eye. Many cases of coloboma of the lens are now on 
record. Heyl (1875), in his paper, sums up twenty-three including his 
own, and in 1893 Bock 5 records forty-six. To these may be added (mostly 
since that date) those reported by Oliver, Iodko, Badal, Becker, Schiess- 
Gemuseus, Cissel, Stephenson, Marple, Hess, Theobald, and Rogman. 
Knapp gives a case where the defect was situated in the upper part of the 
lens, and Rogman has recently described another occupying the same situa¬ 
tion. Iodko, Cartwright, Schaumberg, and Christen each report one where 
it occupied the upper outer part. Bowman, Baas, Schiess-Gemuseus, and 
Hess each record a defect pointing inward, and Schaumberg a second case 
where the notch was upward and inward, Lang and Theobald each de¬ 
scribing a defect pointing outward. In Theobald’s first Qg\e, where the 
notch was at the outer part of the lens, it was possibly t^cj$n#tic, as was a 
corresponding scar in the cornea. In all other repqj^Kf cases the defect 
has been in the lower part of the lens, or in its low«ff\nner or lower outer 
portion. Of course most of these observations been made with the 

ophthalmoscope, but notched lenses have^akQibeen extracted from the 
living eye and examined anatomically, ydjiuk, Bowman 6 extracted a 
notched and dislocated lens on account o^epeated attacks of glaucomatous 
tension, and describes it as “ altogethW too small and too convex. Its 
equator was circular but irregulai^A^a way to give indication of the tri- 
1 inear arrangement of its semgA^-i.6., it approached in a slight degree 
to a triangular outline when seen from the front or back.” Badal 7 also 
extracted a notched lens capsule from an eye with coloboma of the 

iris and chorioid. Its lm^ontal diameter was eight millimetres, its vertical 
diameter sagittal five millimetres. As 

1 Schiess-{XA^eus, Archiv fur Ophthalmologie, 1888, xxi. S. 453. 

2 Meyer^^^etin de la Societe Opht. de Paris, November, 1892. 

3 HeylAReport of Fifth International Ophtlialmological Congress, 1875, p. 16. 

4 Report of Fifth International Ophtlialmological Congress, p. 28. 

K ^ Die Angehorenen Colohomae des Augaepfels, Wien, 1892. 

owman, The Royal London Ophthalmic Hospital Reports, vol. v. Part 1, p. 16. 

..’ a 

xjadal, Gazette des Hopitaux, 1880, p. 459. 



Fig. 12. 

Left eye. 

Teriimclear opacity in each lens, with lateral colo- 
boma of the left; coloboma of the iris in both. (Hess.) 

previously mentioned, the defect may be accompanied by a coloboma of 
the iris or chorioid, but is more often observed without any trace of such 
accompanying lesion. It usually affects both eyes, but in a number of 
cases the fellow-eye has been found entirely normal. In many instances it 
is recorded that the notched lenses were absolutely clear, but there have often 
been observed in them various degrees and forms of cataract. In Knapp’s 
case the opacity was central, in that of Schiess a central capsular spot, in 
that of Cartwright a posterior opacity with retained hyaloid arteries ; in one 

case of Bowman, in one of Gunn, 
in two of Rogman, and in one of 
Hess there was marked perinu¬ 
clear (zonular) opacity. Fig. 12 
shows the location of the notch 
and the form of the opacity in 
the left eye of the case of Hess. 
The fellow-eye, also represented 
in Fig. 12, presented zonular 
opacity without any coloboma of 
the lens. Bowman, in the paper 
already referred to, says, “the inner margin, instead of being a regular 
curve, presents several sinuosities, and takes, on the whole, a horizontal 
direction, as though the lowest part had sprung upward from its attach¬ 
ment to the ciliary body, while the lateral parts are still held by the sus¬ 
pensory ligament.” While this feebleness or defect in th& zonula is prob¬ 
ably the true explanation of some superficial notches,ufoi\)ossibly due to 
imperfect closure of the foetal slit, the deeper notcl^j m the lens, as has 
been pointed out by Heyl and Hess, are probaj^^aused by some con¬ 
genital defect dependent upon an anomalous •ibution of the hyaloid 
artery or of its branches to the posterior le^ySpsule. The exact nature, 
however, of such a congenital defect is differently understood by the 
two authors just mentioned. Heyl holds that insufficient or arrested 
development of some of the vessels G!)tke vascular lens-capsule causes an 
arrest in the development of thjJ0js, while Hess maintains that the defects 
are due to pressure on the idsi^y some portion of vascular foetal tissue 
which has not undergon^^fessive changes and absorption at the usual 
time. Bock also beli^v^0mat the vascular plug of ingrowing mesoderm 
is a hinderance to development at the point of contact, while Bach * 1 thinks 
that the lens a^ Jifjes becomes too large for the secondary optic vesicle, 
and that at tl(ei^oints of contact with the ingrowing mesoderm there 
is sufficie^ft^^essure to cause molecular degeneration of the subcap- 
sular fib^^which undergo gradual absorption and leave a notch ffi their 


1 L. Bach, Archiv fur Ophfhalmologie, xlv., 1, S. 65. 



Fig. 13. 

Lenticonus anterior. (Webster.) 


The anomalies classed as lenticonus consist of a more or less conical pro¬ 
jection of the anterior or posterior surface of the lens. Such formations give 
rise to various degrees of myopia in various areas of the pupillary space, the 
refraction being highest at the apex of the cone, thus producing a state of 
affairs which as regards the refraction of the eye much resembles conical 
cornea. In several of the reported cases 
the defect has been confined to one eye 
only. Webster 1 in 1875 gives a most in¬ 
teresting case where the apex of the lens 
cone projected into the anterior chamber. 

His picture of it is reproduced in Fig. 13. 

With normal pupil a glass —1J gave V. 

= 20/CC, while with dilated pupil the 
periphery of the lens was so flat that + 

1/10 gave V. = 20/XL. In 1880 Van der 
Laan 2 describes a protuberance in the an¬ 
terior portion of the lens occupying about 
one-fourth of its surface. In the centre 
there was high myopia and in the periphery hypermetropia = 3 D. Lindner 
reports a case of lenticonus anterior with ectopia and corectopia. Both 
lenses were dislocated upward and had pyramidal projections on their 
anterior surfaces while the pupils were drawn downwar&C^ 

F. Mever 3 * in 1888 describes a case of posterior lenfplmftis in which there 
was a small opacity at the posterior pole. Kna^Qvy enneman, 5 Eiseck, 
Mitvalsky, Gullstrand, Salzmann, Doyne, JKrcNdge, L. Mueller, and 
Jackson 6 have also observed cases of lenticorfiW posterior. In describing 
his case Venneman remarks that in a ^e^^he central myopia became 
greater, this change corresponding ^\fah^ i rncreased acuity of vision. He 
therefore hoped to see the lenticom^^entually change to a lentiglobus. 
Van der Laan also in the case ataree cited asserts that the lens cone was of 
gradual formation and had laste<LSght years. It is therefore probable that 
in some cases the patholoo nges initiated during the development of 

the eye do not become stak&Jfery but go on to further development. Weeks 7 
and Boosa 8 each d^crfee a case of posterior lenticonus in which there 
was opacity at the apex of the cone. In the patient of Weeks there 
were remnants %T^btal pupillary membrane in the other eye, which was 


1 Webster^ScIives of Ophthalmology, iv. 2, 262. 

2 Var^^^V^aan, Nagel, Jahresbericht, 1880, S. 364. 

3 F. SS^er, Centralblatt fur praktische Augenheilkunde, February, 1888, S. 541. 

aggs, The Lancet, 1891, ii. p. 657. 

ejmeman, Annales d’Oculistique, t. cv. p. 158. 

ackson, Section on Ophthalmology, College of Physicians of Philada., 1894. 

7 Weeks, Archives of Ophthalmology, vol. xx. p. 260. 

8 Roosa, Treatise on Diseases of the Eye, 1894, p. 423. 



otherwise healthy. In Roosa’s case the fellow-eye was normal. Elschnig 
has also recorded a case of marked lentiglobus posterior with slight opacity 
of the parts involved. 

In several of the cases of lenticonus there was a varying degree of 
opacity in the lens, but in the cases reported by Knapp, Venneman, Doyne, 
Hartridge, L. Mueller, Sym, and Cramer the lens appears to have been 
entirely transparent. In one of the two cases reported by Mueller, in spite 
of the reflex image from the anterior capsule being smaller in the centre of 
the pupil, the refraction in the axis of the lens was 2.5 D. less than in the 
periphery, while in his second case the usual relations obtained, the refrac¬ 
tion being higher in the centre than in the periphery. Mueller believes the 
variation in the refraction in the different pupillary areas to be due to the 
shape of the nucleus of the lens, which according to him may be either 
spindle-shaped, giving higher central refraction, or saucer-shaped, giving 
(as in his first case) lower central refraction. 

Pathology of Lenticonus.—With the exception of the case of Per- 
gens, 1 who found lenticonus posterior in the buphthalmic eye of a four- 
and-a-half-year-old child, w~e have no anatomical investigations of this 
anomaly as occurring in man, and in default of this we must turn to simi¬ 
lar conditions found in the lower animals. Becker 2 describes a conical 
projection on the posterior part of a rabbit’s lens which was apparently 
everywhere covered with capsule and in which the lens-fibres although 
abnormally arranged were transparent. Hess 3 has since published accounts 
of two such malformations, one from the eye of a pig, thetother from the 
eye of a rabbit. These are well shown in Figs. 14 andH^ In each there 


Fig. 14. 

Lenticonus in rabbit’s 
eye. (Hess.) 

Lenticonus in pig’s eye. J& 

(Hess.) _Ov 

>n£^ > 

is an irregularly globulaoifcojection from the posterior part of the lens 
covered by a very thi^ctpsule, which in places is imperfect and wanting. 
The lens-fibres exhii^teoan abnormal course and marked granular degener¬ 
ation, and in neid^Sfrase was there any formation of a nucleus. The an¬ 
terior portion ^^ach lens was transparent, with normal capsule and capsu¬ 
lar epith~ 14 ^^ T 


it epith^J^i^S In the case of the rabbit the fellow-eye presented a nuclear 
itaract* jMore recently Hess has had an opportunity of examining eight 


1 Pergens, Archiv fiir Augenheilkunde, xxxv., 1, S. 1. 

2 Becker, Anatomie der gesunden und kranken Linse, S. 125. 

3 Hess, Archiv fiir Ophthalmologie, xlii., 3, S. 234. 



lenses where the nucleus was not central, but lay close to the capsule either 
at the posterior pole or between it and the equator. In some the outline 
of the lens was regular ; in others the cone was caused by the nucleus pro¬ 
jecting backward; in others again a layer of lens-fibres had applied them¬ 
selves over the projecting nucleus. The posterior capsule was usually intact, 
but in a few instances was apparently ruptured in foetal life between the 
posterior pole and the equator, and there was a rounded irregular mass of 
lens-fibres projecting backward out of the cleft. Bach 1 2 3 reports three cases 
of lenticonus posterior in the eyes of rabbits, in all of which the lenses 
were partly cataractous. In these he found a connective-tissue band, due 
to the thickened sheath of the central hyaloid artery, which by shrinking 
and pulling on the posterior capsule of the lens seems to have caused its 
thinning and rupture as well as either a conical or globular projection of 
the posterior part of the lens. 


Every ophthalmic surgeon has certainly at times in examining enucle¬ 
ated eyeballs had an opportunity to see deformities of the lens, where, either 
from its elasticity or perhaps from pressure upon its equator, the lens, par¬ 
tially or completely dislocated, has become more or less globular in form, 

lorn a of t^e^iWa with secondary glaucoma 

and ma»&^i^n crease in the diameter of the ciliary circle, while Fig. 18 
r% the deformity of the lens caused by pressure from an intra- 

1 Bach, Archiv fur Ophthalmologie, xlv., 1, S. 59-60. 

2 Iwanoff, Archiv fur Ophthalmologie, 1869, xv., 2, S 21. 

3 Hocquard, Archives d’Ophtalmologie, April, 1894. 



Fig. 17. 

Fig. 18. 

ocular tumor. Ridley 1 found a circular projection on the anterior surface of 
the lens in two cases of glaucoma, which he thinks due to pressure of the 

sphincter of the iris on a softened lens. 
He terms this deformity “ moulding of 
the lens;” while Fig. 19, from Becker, 2 
shows a much distorted lens, the equa¬ 
torial region of one side being much 
thinned and elongated, projecting into 
a staphyloma at the corneo-scleral junc¬ 
tion. Ulcers of the cornea occasion¬ 
ally give rise to hernia of the lens. 
Where they are peripheral they are 
covered by iris, but when central the 
lens alone presents, and its transparent capsule and anterior layers, thus 
protruding, resemble very much a hernia of the membrane of Descemet. 

Flattening of the 
lens in case of sta¬ 
phyloma of the cor¬ 
nea. (Hocquard.) 

Deformity of lens 
caused by pressure of 
an intra-ocular tu¬ 
mor. (Hocquard.) 

Fig. 19. 

Distorted lens. (Becker.) 

Fig. 20. 

Her 1 

the lens with intact capsule. (E. Treacher Collins.) 

Fig. 20, from^^icher Collins, 3 gives an interesting example of such a 
hernia of^t^y^ens with an intact capsule. Of course any rupture or cut 
of the capsule, owing to swelling of the lens substance, gives rise to 

* rs^piey, Transactions of the Ophthal. Society of the U. K., xiv. pp. 138, 146. 
^VBecker, Anatomie der gesunden und kranken Linse, S. 125. 
er Treacher Collins, The Royal London Ophthalmic Hospital Reports, vol. xii. p. 342. 



irregular projections from its surface corresponding to the extent and 
location of the injury. 



In all ages opacities in and back of the pupillary space have attracted 
attention on account of the altered appearance of the eye and of the diminu¬ 
tion of sight accompanying them. The color, consistence, and surface aspect 
of those pathological conditions in which the pupil had lost its normal 
black hue were designated with a variety of names in various languages, 
most of which were not only an attempt to describe those changes, but in 
many instances also an endeavor to indicate the opinion which was held as 
to their causes. The history of medical opinion, therefore, as to pupillary 
opacities, as given in detail by Sprengel, Hirsch, and Magnus, are interesting 
not only as showing the slow development of scientific knowledge, but also 
as affording most instructive instances of the dangers of theoretical reason¬ 
ing on facts and data where we have no understanding of the minute 
anatomy and physiology of the tissues concerned. Magnus shows us that 
among the Egyptians, the Greeks, the Jews, and the Arabians all such 
opacities were classed as effusions, and in consequence hypopvon and inflam¬ 
matory plastic exudations were confounded with the varh^\pacities of the 
lens, and in some of the old books we are directed to/SMke the head of the 
patient violently to enable us to see whether the cloi^j^ dissipated or altered 
in its appearance by this procedure. The talked of “the rising 

of water in the eye,” an expression which^p^und again in the Greek 
u7ro/u/ia f from vnozeiD (to flow from beneafffiv^diile the Hebrews spoke of 
“ stationary water in the eye.” The ganrMuea is again encountered in the 
Latin word suffusio. Based on si/Cm^ideas of pathology, their surgical 
remedial measures were of two v^iefcfes—preventive and curative. 

I. Preventive Measures.-^jmnong most of the nations of antiquity 
these procedures consisted^fD^iSn a division of the vessels of the forehead 
and temple as would in th^ opinion prevent either a descent or a welling 
up of water within /BeNdipil. This division was usually effected by inci¬ 
sions in the skin, caMed down to the bone; and the subsequent healing 
and re-formatibu of the vessels was retarded by the use of tents or by 
scraping of iX^bone or by actual cautery. The Chinese and Japanese are 
said to h^v^i^d a preventive surgical treatment consisting of acupuncture 
follow&Qj^ actual cautery, believing that cataract and most other diseases 
are {Ita to an interference with the circulation, which they try to stimulate 

^ TI. Curative Measures.—These consisted in acupuncture to let the 
er luid matter out from the eye, or, if it proved stiffened and hard, to push it 




out of the pupillary space, and where this proved impossible, to lacerate or 
incise the remnants in the anterior chamber or in the pupillary space. So 
have arisen the various methods of couching and depressing cataract, for 
which we find inexact descriptions in the earlier authors, but which in the 
time of Celsus had become definite and precise. The Indian method of 
couching as described by Breton 1 in the present day appears to have come 
down by example and practice from gray antiquity. The most astonishing 
circumstance in connection with these long ages of the practice of depres¬ 
sion or dislocation of cataract is the persistence with which its practitioners 
held on to the theory of effusion, in spite of the fact that in many instances 
their daily practice must have convinced them when the lens broke up, or 
still more when it was dislocated into the anterior chamber, that it was 
really a solid, rounded lenticular body, and not a shrunken and condensed 
mass of pupillary effusion. Such pathological ideas, however, in more or 
less modified shape remained dominant until Brisseau, in 1705, read a 
paper before the Royal Academy of Medicine in Paris, in which he demon¬ 
strated to an unwilling and unconvinced audience that the true seat of 
cataract lay in the lens itself. A few years later, Maitre Jean, 2 who had 
already in 1692 convinced himself that the opacity lay in the lens, by ob¬ 
servation of cataracts which he had luxated into the anterior chamber 
during attempts at depression, and especially by an autopsy of two eyes in 
which he had successfully performed the depression of cataract, published 
his work on Diseases of the Eyes, and succeeded better in arousing the 
attention of the medical world and convincing some at least of his con¬ 
temporaries. The word “ cataract” according to Hirsch i^wsts first used in 
1150 by Matteus Platearius of Salernum. According^ysome authors this 

* in to the eye, 



xaTaprjyvu/iiy to break 
xarapa(T(ra to disorder 


is only another method of expressing a fall of v 
deriving the word from xarapaxT^q^ a waterfall 
violently; while others insist that it comesfY^i 
violently. ,o x 


The word “ cataract” has nowj0pne to mean any opacity in the lens or 
its capsule, although the latterjQkriety is usually qualified by the word 
“ capsular.” The writers period when dislocation of the lens into 

the vitreous was almost the (>my operation practised for the relief of cataract 
were in the habit of a^ljjig the opacities which remained in the pupillary 
space capsular cata^t; and Malgaigne in 1841 raised quite a storm of 
criticism by deckTTikg that there was no capsular cataract. Although, as 
will be shqv^Qmer and was first demonstrated by Arlt (1855), opacities 
and thick%^ingk of the capsule can be observed in many cataracts, never- 

, Trans, of Med. and Phys. Soc. of Calcutta, 1826, vol. ii. 

. Maitre Jean, Traite des maladies de Tceil et des remedes propres pour leur 

gi^teon, Troyes, 1707. 

A<zr Hirsch, Klinische Monatsblatter fur Augenheilkunde, 1869, S. 284. 



theless Malgaigne was right in believing that most of what was then 
thought to be capsular cataract was really part of the lens itself which had 
adhered to the capsule and had become opaque from the action of the 


In congenital and in traumatic cataract we find partial and irregular 
opacities in various parts of the lens, but in the cataracts which develop in 
eyes previously normal and endowed with good vision the opacity usually 
commences either as opaque stripes in the equatorial cortical substance or 
as a perinuclear cloud. We will best understand the development of cata¬ 
ract if we glance at the lens at birth and study its growth and changes in 
adult life. According to Jaeger the average lens at birth measures 4.525 
millimetres in antero-posterior, but only 6.345 millimetres in its equatorial 
diameter. In adult life the autero-posterior diameter remaining nearly the 
same, the equatorial has grown to 9.150 millimetres. In infancy the lens 
tissue is colorless and transparent and the index of refraction in the deeper 
parts of the lens is so nearly that of the superficial layers that it takes 
careful examination with oblique light to demonstrate its presence. During 
adolescence new fibres are constantly produced by the epithelium of the 
anterior capsule, which push their way around the equator and up towards 
the posterior pole, while the mass which constituted the entire lens at birth, 
having exhausted its developmental powers and pressed on by the newly 
formed fibres, becomes denser in consistence and assurafeka pale straw- 
yellow color which is usually quite perceptible by age of twenty. 
Owing to the presence of this dense centre the lens/Meomes less elastic and 
less capable of assuming greater curvatures offsfrrface under the influence 
of the ciliary muscle. We find therefore, ev^^n early childhood, as soon 
as children are sufficiently educated to be^aKkjto give reliable answers, that 
we can demonstrate a rapid diminution i^iire power of accommodation with 
a recession of the near-point. The s^Wth of the nucleus continues steadily 
during health, in consequence of theNieeper layers of cortical fibres, each in 
turn, becoming denser, more yei&y, and adhering to the central mass. In 
fact, when in consequence or impaired nutrition this process stops, 

the first step has been tal|bm£mvards the formation of a cataract, although in 
some cases, usually kl* advanced old age, after the entire lens has become 
sclerosed, we find it ^Transmitted light of a rich reddish-brown color with 
sufficient degeneration of the fibres to dim the images formed by it, and 
we have a statjQniich, owing to its interference with distinct vision and to 
the small^^^atint of light reflected from the pupil, is known as black 
cataracOS^Naracta nigra), a form, however, entirely different from that 
whiqlAis sometimes found after hemorrhages into the eye where blood-coloring 
n^^r has been absorbed by the lens. In adolescent and adult lenses 
^fcbere is considerable difference in the index of refraction of the different 
& iyers, and therefore, when we examine such healthy eyes with oblique 



Fig. 21. 

Stella of normal lens. (Tweedy.) 

light and at the same time study the lens with a magnifying glass, we see 
the sectors appearing grayish and the intersectorial divisions as dark lines 

dividing them. The direction of these 
lines varies in different individuals and 
even in the same individual at different 
times of life, their ends becoming more 
branched as age advances. Fig. 21, 
taken from Tweedy, 1 gives a good ex¬ 
ample of the anterior stella of a healthy 
adult human lens as seen with dilated 
pupil and the use of a magnifying glass 
and oblique light. Fridenberg, 2 who 
examined many healthy lenses with 
binocular magnifying glasses and ob¬ 
lique light, found that out of one hun¬ 
dred lenses about one-fifth had four pri¬ 
mary rays, two-fifths five rays, one-fifth six rays, and one-fifth seven rays. 

JEntoseopie examination casts a most interesting light on the structure of 
the healthy adult lens and displays its sectors as well as various shining or 
opaque dots throughout its substance, and almost every one who wears 
spectacles has frequent opportunity for studying his own lenses by the dif¬ 
fusion circles arising from some brilliant point of reflection on the frames 
of his glasses and consequently from a point inside of the range of distinct 
vision. ^V 


It is important to consider attentively the^ ^cts, first, as seen en- 
toptically, and, second, as demonstrable by trq/Ewitted and reflected light. 
The lens spectrum is readily seen when wejcraiit to the eye a small, in¬ 
tense beam of homocentric light such al^s obtained by looking through a 
half-millimetre aperture in a metal pl^ on which a bright beam of light 
is concentrated by a condensing m Listing, Helmholtz, and Donders 
have given us instructive picturCgXf their own lenses as seen in this way, 
and describe, first, pearl do^Jmh bright centre and dark edges or rims 
which lie mostly near th& ^nkrior capsule; second, opaque or slightly trans¬ 
lucent spots which are sometimes round, at others irregularly angular; 
third, radiating line^iwhich correspond with the intersectorial lines of the 
lens as seen with/Sykted pupil and oblique light when the lens is studied 
with a magnifying glass. Owing to the intense illumination obtained in 
the manner above described, the pupil contracts and the field is narrowed 
unless w4 Mve recourse to a mydriatic to hold the pupil dilated. This 
incoi^e^i^ice may be avoided by the method which is hereafter described, 


1 Tweedy, R. L. O. H. Rep., vol. viii. p. 25. 

2 Fridenberg, Arcbiv fur Augenheilkunde, xxxi. S. 293. 



because the comparatively feeble illumination and the dark room secure a 
semi-dilated pupil and wide field. The lens spectrum can then be more 
readily observed by taking as the sources of light the images reflected 
from the posterior and anterior surfaces of a convex lens of 20 D. If in 
a dark room with only a single source of illumination, and this placed 
behind and to one side of the observer, we regard these brilliant but minute 
images through a lens of — 20 D. held in a spectacle-frame close to the 
eye, we thus obtain a pencil of divergent rays, and the lens spectrum ap¬ 
pears as a disk composed of bright dots lying close to each other but not in 
contact, the interspaces being comparatively less illuminated, and we usually 
find a few “ pearl spots/’—that is, larger bright spots surrounded by a dis¬ 
tinct dark ring. We also see bright radiating lines corresponding with the 
intersectorial lines of the lens, each line being slightly tortuous and in 
places more or less beaded in outline. If now we remove the concave lens 
from the frame and insert in its place a convex one of -f- 20 D., we obtain 
a pencil of convergent rays and a very different picture. What previously 
appeared as bright dots now look like clear, darkish round spaces surrounded 
by a bright rim. Both the smaller dots and the large pearl dots have this 
appearance. The radiating lines have almost disappeared, but attentive 
study shows that they may be traced as darkish stripes with brighter edges. 
In some lenses, however, the dark radiating stripes are bordered by 
sharp-cut bright lines on each side. All these appearances are best seen 
when the lens used in reflecting the images is held at such an angle as to 
appear as a faint whitish illuminated cloud, and we have ^rabst instructive 
comparison of the brilliant image furnished by the ne^Jb^ion of the pos¬ 
terior curvature of the lens with a fainter image fr^ffo^ne anterior surface. 
By slight movements of the lens which servothe source of light, 
towards the observer’s eye and away from may make the dots and 

stripes alternately sharper and more All these appearances are 

more instructive when we compare tli^mVaach those of young and healthy 
lenses when examined with the opMualmoscope, the pupil having been 
dilated and a lens of + 20 D . placedSfehind the mirror. Thus seen, every 
crystalline lens looks more or l^fcj^gl’anular, and in some are seen a few clear 
round spaces surrounded Iw £ hair-like black outline. These are sometimes 
close to the intersectorialN^es and send hair-like prolongations to them, 
but more frequently M\4jheir seat in some other part of the lens, usually 
close to the anterioi\a*psule, and probably correspond with the pearl dots 
as seen entoptic&BCj In examining numbers of presumably healthy young 
lenses it is astc^^Ring how often slight but distinct remnants of the foetal 
pupillary^bmbrane are visible. In a series of eleven hundred and eighty- 
four coJ^^tive cases who came for error of refraction in my hospital ser¬ 
vices tomr who were carefully examined for lenticular opacities with the 
o^ff|iHmoscope armed with a 20 D. lens behind a mirror, seven had corner 
eloudy that the state of the lenses could not be definitely ascertained, 
the remaining eleven hundred and seventy-seven, nine hundred and 



sixty-nine had clear lenses, one hundred and sixty presented either minute 
ring spots or black dots, one had central anterior polar cataract, eighteen 
showed striae of commencing cortical cataract, while in twenty-nine there 
were present traces of persistent pupillary membrane. As regards the time 
of life of individuals examined, nine hundred and thirty-three were under 
thirty years of age, and of these one hundred and thirty presented either 
rings or black spots in the lens, while the striae of incipient cataract were 
found only in those over thirty years of age, and eighteen times in two 
hundred and forty-four individuals. According to Pulvermacher, 1 in sixty 
children under ten years of age with entirely normal eyes the magnifying- 
glass behind the mirror showed in twenty-six—i.e., forty-three per cent.— 
lens opacities, consisting of distinct spots and vesicles. 

Besides the above-mentioned clear dots and granular appearances we 
often find irregularly-rounded minute and partially opaque spots, which 
presumably also are indications of want of absolute transparency in the 
lens tissue, probably congenital and not due to post-natal pathological 
change. When the lens is studied by a strong magnifying-glass and oblique 
light, we obtain a grayish reflex from its substance, while the intersectorial 
lines appear dark, and some of the large ring-shaped bodies previously 
described appear grayish or whitish. Fig. 22, from Donders 2 (reduced 
one-half size), gives a good view of the lens spectrum from the right eye of 
this illustrious observer at the age of forty-five. Darier 3 has lately pub¬ 
lished instructive entoptic pictures of his own lenses and those of some of 
his friends. He employs to produce them a concave lei\sjpf 30 to 40 D., 
through which the experimenter looks W\ajcandle distant 
five metres. After adult life the grows but slowly. 
The accompanying diagram, Fig. &rrom Priestley Smith, 4 
shows the average increase §fi<Q^ze between the ages of 
twenty-five and sixty-fivej0r£nses which have remained 
healthy and transparent.^ Tjjjtie increase in size with advan¬ 
cing years is accompanied by a steady gain of weight. 
Fig. 24, taken from\iJ^e same observer, is so arranged as 
to show the siz( weight of lenses at different ages by 
their displacement of water. JA^gures at the left-hand side of the diagram 
indicate the weight as shtf^M^y displacement of water, while the ages are 
indicated in the line oa) bop of the figure. One hundred and fifty-six 
lenses taken from th^^s of ninety-one individuals were examined, and it 
appears that the $^^it of the lens increases 4.5 milligrammes in each decade 
of life. The (Mtpin the figure indicate clear lenses; the circles, lenses 
which wem™Jd to be more or less cataractous. The same author 5 shows 
that lena^s^hich have become cataractous are smaller and weigh less than 

Fig. 23. 

Growth of lens 
between the ages 
of twenty-five and 
sixty-five. (Priest¬ 
ley Smith.) 

\^onaers, . 

jermacher, Centralblatt fur prakt. Augenheilkunde, 1894 (Supplement), 

-^onaers, Anomalies of Accommodation and Refraction, p. 200. 

3 Darier, Ann. d’Oculistique, September, 1895, p. 198. 

4 Priestley Smith, Trans. Ophtli. Soc. U. K., vol. iii. p. 88. 

5 Ibidem, p. 85. 



do healthy lenses at the same time of life. These statements have been 
confirmed by Collins, 1 who tells us that the average weight of ten clear 
lenses was 0.204 gramme, while the average of six with beginning cataract 
was 0.113 gramme. When, owing to failure of the general health or patho¬ 
logical changes in the vessels of the interior of the eyeball and the gradual 
exhaustion of nutritive force in the capsular cells, the lens ceases to increase 
in size and density, then the newly-formed fibres are no longer pushed tightly 
up against the nucleus, and spaces arise between the lens-fibres which be¬ 
come filled with serum. They are usually first formed in the cortical sub- } 
stance, either just outside of the equator of the nucleus or in the extreme 
periphery of the lens, in the position where growth is normally most active. 
The fibres of the cortical masses themselves swell slightly from imbibition 
of this endosmosed fluid and commence to undergo molecular degeneration, 
and when these processes manifest themselves in the part of the lens corre¬ 
sponding to the pupillary area, they deflect and impede the passage of light 
to the retina, and we have a diminution in the acuity of vision. At this 
stage patients turn to the doctor for relief, and examination shows them to 
have incipient cataract. The subjective complaints which lead patients to 
seek relief are usually those of early fatigue of the eye, dim vision, motes 
or specks before the eyes, and the seeing small and distant but brightly il¬ 
luminated objects irregular in outline and double. The patient complains 
perhaps that his glasses no longer suit him, and that the moon looks unnat¬ 
urally horned or double. Examination with the test-letters will show that 
in strong light the acuity of vision is still not far from formal, and that 
perhaps the correction of some small astigmatism produce^by the unequal 
swelling of the lens will improve it. The defects o|"N3§m are more tangi¬ 
ble in near work, and while glasses enable the pafcj&^to read fluently ordi¬ 
nary print, still Jaeger 1 is not deciphered at ^Hjkpfoper distance and print 
of any size soon tires the eye. When, swelling of the anterior 

cortical, the iris is pushed forward anterior chamber reduced in 

size, the strong light of the sun out-oj^)ors becomes very disagreeable to 
the patient, and he usually avoids or Moderates it by the use of a shade and 
dark glasses. Day by day and ] by month, as the lens becomes hazier, 
the dimness augments and amount of useful vision decreases until, as the 
cataract ripens, a dense ft^^settles down on all objects and even bright 
sunlight has a moonjaglnpallor. Even after all useful form vision has 
disappeared, patients^vijl often recognize large patches of bright and well- 
marked colors, ^l|j3^ugh in many the great yellowness of the nucleus di¬ 
minishes theiiywKi’er of distinguishing the lighter shades of blue. Even 
in advanced^h^Ss the patient is still able to perceive bright points of light 
and to^ram^nze the shadows of objects held in front of him. Besides the 
slighLirraability of the eye above mentioned and faint sensations of un¬ 
easiness, and discomfort, there is usually no pain in uncomplicated cataract. 


1 Treacher Collins, Ophthalmic Review, 1889, p. 321. 



When we examine objectively eyes affected with incipient cataract there 
is usually a marked diminution of the normal blackness of the pupil, and 
often a small pupil with a narrow anterior chamber. The pupillary re¬ 
actions are prompt, but the dilatation of the pupil under influence of a 
mydriatic is almost always less than that produced in healthy eyes of per¬ 
sons of the same age, and in many instances, owing apparently to some 
degree of atrophy of the iris tissue, a dilatation of four to five millimetres 
is all that can be obtained, and this dilatation is often accompanied in such 
cases by marked pericorneal flushing of the eyeball and of the bulbar con¬ 
junctiva. When we look into the pupil thus distended we obtain a gray 
or grayish-yellow reflex most marked from the deeper layers of the lens, 
while if we inspect the pupillary area minutely with a magnifying-glass we 
often obtain a mother-of-pearl glitter from the fibres of the anterior cortical, 
while the striation of the lens-substance is so arranged that the individual 
sectors show distinctly. Gray spots and streaks are often visible, which 
may be rounded, ovoid, linear, or irregularly pyramidal, the latter being 
usually situate in the periphery of the lens. They lie in either the anterior 
or the posterior cortical or in both, sometimes next the capsule, sometimes 
deeper, usually at the extreme periphery of the lens, or at times near the 
equator of the nucleus. The exact shape of all such opacities is still better 
seen by using -f*16 D. or -f- 20 D. lenses behind the ophthalmoscopic mirror, 
and we can thus discern that the spots and streaks are irregularly rounded, 
spindle-shaped, or pyriform, while we can usually see throughout the lens 
infinitesimally small dotted opacities, more marked in thetcortical layers. 
The opacities which appeared gray by oblique light now .s{Km as dark spots 
on a yellow-red'field, as they intercept and deflect from^jjnKeyes the returned 
light from the illuminated eye-ground. As the catp^&Eincreases in density 
less and less light penetrates the fundus and ^^eturned from it, so that 
eventually all red reflej-JStem the eye-ground is lost. 
The accompanying /citt/%Fig. 25, shows an excep¬ 
tional case wheifc vm sectors had become opaque, 
but red light stij^mne through the intersectorial lines 
and through/Ae periphery of the pupil. As the cata¬ 
ract ripenQ&e lines become opaque and show with 
reflec^ as dense white lines, while the anterior 

cortksy^becomes more and more opaque, until finally 
Sectors of lens cloudy flie posterior pupillary margin of the iris appears to rest 
^c^rianiiie^ r ^Twee^y r ^^^^^^ u ^^ T on the °P aci ty of the anterior cortical and the 

Q v 'clear space separating the latter from the uvea has dis- 
^ s stage the lens has generally lost its swelling and the 
wjber has reacquired its normal size or perhaps become a little 

Fig. 25. 


er* ar^tl 

deeper^ar^the cataract is said to have become ripe. All cataracts, how- 
ever^Anot reach this stage, but some remain always limited to the perinu- 


1 Tweedy, R. L. O. H. Rep., vol. viii. pp. 24-36. 



clear layers, so that, examined with the ophthalmoscope, tiiey show a grayish- 
black mass lying deep within the lens, with a cortical that is so clear that 
with dilated pupil the red light from the eye-ground returns freely all 
around the periphery of the lens. The above-described changes are so im¬ 
portant and have been so well studied and pictured by Jaeger and by 
Magnus that graphic illustrations of the latter author are here reproduced. 
Fig. 26 (Taf. III. of Magnus) shows a case of commencing cataract where 
irregularly rouud, ovoid, or pear-shaped figures may be seen in the equator 
of the lens, with large pointed shoots advancing towards the pole. Fig. 27 
(Magnus, Taf. IV.) shows a still more advanced form of equatorial corti¬ 
cal cataract where the individual spaces of degeneration are larger, and 
where there are also round and ovoid figures in the cortical nearer the pole, 
while some of the spaces between the sectors show as strings or lines of 
varying diameter. It has been the experience of the author that cortical 
cataract in the majority of instances commences in the inner lower quadrant 

Fig. 27. 

Ftg. 28. 

Fig. 26 

Incipient cataract. (Magnus.) Incipient cataract. (Magnus.) 


of the lens. Fig. 28 (Taf. XI. of Magnus) repr^jRs slight opacities in 
the equatorial cortical, and much more marked/iStear, spindle, and irregular 
ones in the zone surrounding the equatoi/oFyfc^e nucleus, while irregular 
dots and elongated figures occupy the mfcnNs^ntral cortical. Cataract may 
also commence in the anterior or postelvh’ pole of the lens, usually either 
as irregularly shaped masses of opiuajf;y or as linear or oval figures. Where 
such masses are at the poster io|*Nj>ne they very commonly have star-like 
prolongations in the postei^o^^SKical, extending outward towards the 
equator of the lens. Whej^ f|Vis is the case the eye-ground should be care¬ 
fully examined for retirfre-|h^rioidal changes, if this is still practicable with 
dilated pupil, and if no^Aie field of vision carefully tested. According to 
Magnus the first &$jrjptrances of senile cataract are to be found in the cortical 
substance close ^tOjlio equator in 82.69 per cent, of all cases; in the poles of 
the lens in ^^jpbr cent., and in the perinuclear cortical in 7.69 per cent., and 
daily cliil^^experience bears him out in the statement that the first indica¬ 
tions of\change are most often found in the peripheral posterior cortical. 
Wh^P^n|ng, broad shoots intrude on the pupillary space oblique light and 
J^naghifying-glass will at times show a folding of the lens-capsule. A ripe 

OyHftract usually presents slight clouding of the thin layer of pupillary anterior 
V Vol. IV.—19 




cortical, while the large, yellow, waxy-looking nucleus comes up close to the 
surface, aud at this time or a little later white opaque spots are often formed 
immediately under the capsule and in the superficial layer of lens-fibres. 
These are caused by epithelial proliferations with subsequent degeneration 
of the cells and are known as capsular cataract. After this stage is passed 
the fibres of the nucleus undergo a little further granular degeneration, 
while the cortical softens and either remains slightly yellowish or becomes 
in some instances entirely opaque, whitish, and milky. Where this soften¬ 
ing proceeds to any considerable extent we have a loose nucleus floating 
about in the capsular sac, hidden usually more or less completely by the 
white and fluid cortical. By tilting the head forward we may often cause 
the nucleus to approach the anterior capsule sufficiently to permit its yel¬ 
lowish color and some part of its outlines to be distinguished. This stage 
is called Morgagnian cataract , and an admirable colored illustration of it is 
given by Beer. 1 Sometimes cholesterine crystals form in the degenerating 
lens-matter, and we have the curious spectacle of a shining, glittering mass 
of crystals within the lens-capsule. Where in the very commencement a 
cataract becomes whitish and milky, we have good ground to suspect not 
only that the exterior layers are fluid or semi-fluid, but also that there is 
accompanying disease of the interior of the eye. When the degenerative 
changes in the lens which have produced cataract go on and the patient 
lives long enough, in some instances further changes may occur which re¬ 
sult in restoration of sight. The lens may so far liquefy and absorb as to 
leave only a small remnant of it in the capsule, or the cjfosule may burst 
and the semi-liquid lens-matter thus discharged into ueous may ab¬ 

sorb, or, as we have already seen in speaking of diskMjlon of the lens, there 
may be a spontaneous sinking of it into the vitreous Humor. The two former 
methods of termination will be more minute^Gj^cussed under the head of 
«Second Sight," It must, however, tafcjQmeans be supposed that the 
above-described changes in the lens other without halt or in any 

given period of time. Nothing can jX^more uncertain and various than the 
rate of development and formation o^ataract. It is often for long periods 
nearly stationary, and then opqC&iore, at times without any evident cause, 
goes on to further developnraM) Of course, any severe sickness or any in¬ 
tercurrent inflammation ^N^te eye tends to hasten its development. I or 
practical purposes, kovOer, we must not rest satisfied with the diagnosis 
of cataract and of tWftage of its development, but must endeavor to find 
out the state optic nerve, retina, and other structures in the interior 

of the eye, in (rjjer to ascertain whether its removal is likely to be of advan¬ 
tage to tf^Ohtient. In the very earliest stages, where the opacities are 
mainly situated in the periphery of the lens, we may study the eye-ground 
witl^toieophthalmoscope, and any one who conscientiously looks for such 
l^t^uiar changes in senile eyes will be surprised to see how very fre- 

1 Beer, Lehre von den Augenkrankheiten, Bd. ii., Wien, 1817. 



quently they occur, even in eyes which have given their possessor no incon¬ 
venience, and in which there are no other pathological changes visible with the 
ophthalmoscope. In more advanced cataract the view of the fundus oculi 
will either be insufficient or entirely shut off, and we must rely on the ex¬ 
ternal appearances of the eyeball, its tension, and the promptness of light 
perception and extent of the field of vision for further information as to 
the condition of the interior of the organ. The cornea should have its 
normal polish and transparency. In many instances it may have marked 
arcus senilis without any detriment to the course of healing after operation. 
Any disease of the conjunctiva or of the lachrymal sac is a most unfa void¬ 
able complication. The iris should not only be prompt in its reaction to 
light, but the pupil should dilate readily and to a fair extent under the 
action of a mydriatic. A sufficient degree of atrophy of the muscular con¬ 
stituents of the iris to prevent fair dilatation is an unfavorable sign, indi¬ 
cating often other changes and degenerations in the uveal tract. F ulness of the 
anterior scleral veins and a tension either much below or much above nor¬ 
mal are also unfavorable signs. The most important tests of the condition 
of the interior of the eye are the promptness of light perception and the ex¬ 
tent of the field of vision. In most ripe cataracts, in a perfectly dark room, 
a glimmer of light can be perceived from a candle-flame held at a distance 
of fifteen to twenty feet. In some very dense opacities, such as the early 
stage of Morgagnian cataract, we may have to approach the light to a dis¬ 
tance of ten or twelve feet before it is recognized, and the eye may, never¬ 
theless, have a fairly healthy retina and optic nerve. Thq^mmination of 
the cataractous eye by the use of Foerster’s apparatus^** determine the 
amount of light perception would probably give more^^wrate results; and, 
according to Trompetter, 1 when the eye is placed in auman apparatus at a dis¬ 
tance of eighteen inches from a normal candle, lalf such eyes perceive 

the light of an eighteen-millimetre square opsdvJ; at first, but after sojourn 
in the dark the perceptive power rises, an\Jjght from an eight-millimetre 
square opening is recognized. Where tho^m^ning has to be increased to thirty- 
two millimetres square to obtain K^hVqierception, the cataract is certainly 
complicate. Under any circumstomps, however, a fairly intelligent patient 
will, in spite of the great dimness and blurring of the image, appreciate that 
two sources of light exist wn^vtwo candles or wax tapers are held at a dis¬ 
tance of eighteen inche^4iX^>nt of his eye and then are separated from each 
other. Where he is nmdr to fix one of these, a second shine or glimmer will 
usually be perceivedGkmi the other as long as the moving candle still throws 
a sharp and distj^^image on his cornea. AVhen any difficulty as to obtain¬ 
ing good fiv^Qvexists the patient can be helped by making him point with 
his fingei^^h’ds the central candle, or, if necessary, he can be made to hold 
it himsdf.^ In this way we not only measure the field of vision, but by 
ask^jgv^iich is the brighter light can obtain some idea of the state of cen- 

Trompetter, Klinische Monatsblatter fur Augenheilkunde, 1880, S. 84. 



tral vision. If the peripheral light be the more distinct, we have either an 
unusual density of the nucleus with comparatively clear peripheral cortical, 
—a state of affairs which we ought readily to recognize by the use of oblique 
light,—or else we have some diminution of central vision due to changes in 
the interior of the eye. Of course, such information, as far as we can obtain 
it, is most valuable, and certainly every surgeon of experience has at some 
time been disagreeably surprised by finding that after a successful operation 
for the removal of cataract no useful vision exists, owing to extensive macu¬ 
lar changes. The diffusion of light by the opaque lens is so great that we 
cannot even with the greatest care map out minute changes in the interior 
of the eye or even demonstrate the blind-spot; but we can at times recog¬ 
nize coarser changes, such as a considerable detachment of the retina or the 
total abolition of central vision. 


It has long been known to physiologists that toxic doses of various 
substances introduced into the general system either subcutaneously, or by 
direct injection into the blood, or by ingestion in the stomach, will at times 
produce cataract. Thus, Kunde, 1 in 1857, shows that either common salt 
or nitrate of soda introduced into the large intestine or under the skin of 
frogs would produce cataract, and that the same substances caused similar 
effects in kittens and in dogs. He also found that strong solutions of sugar 
under like circumstances produced cataract, and that in^rags the opacity 
of the lens would clear up when the animal was ggpn put into water. 
Anatomical examination showed him that fluid^SQka spaces had formed 
between the lens-fibres, and that the fluid in jT^TTyhad a different index of 
refraction from that of the lens-fibres theira^&es. Kuehnhorn, 2 in 1858, 
substantiated these experiments, and att/iB™^! the cataract to the influence 



these circumstances the lenses only cloud when the solution contains at 
least two and one-half per cent, of salt or five per cent, of sugar. Heubel 1 
claims that all materials which have a strong affinity for water when intro¬ 
duced into the circulation produce cataract, and that Guttman is mistaken 
in supposing that potassium chloride and calcium chloride do not. The 
former passes off rapidly by the kidneys, and both soon prove fatal to the 
animal by heart-paralysis; but both, when introduced into the conjunctival 
sac or into the anterior chamber, cause prompt clouding of the lens. 
Heubel, by such local application, produced thirty cataracts in animals, 
and, extracting these lenses, compared them with the sound lenses on the 
other side. He found that in all cases the cataractous lens contained less 
water than its fellow on the other side, and that the more extensive the 
opacity the greater was the loss of water. He maintains that similar 
processes take place in all animals, differing slightly in form according to 
the normal build of their lenses and the direction of the sectors. Similar 
opacities to those produced by the articles mentioned result from the use of 
menthol and naphthalin. Bouchard, 2 in 1887, was the first to call atten¬ 
tion to the interesting effects on the eyes caused by the ingestion of naph¬ 
thalin. Kolinsky, 3 in 1889, gives us a minute study of its effects. He 
found that it acted on all inward parts, the smaller the animal the greater 
the effect of any given quantity of the drug. The cataract appears always 
to be secondary, and dependent upon changes in the ciliary body, the 
vitreous, the retina, and the chorioid. The first lesions obsepql are hemor¬ 
rhages into the ciliary body and into the chorioid. The^gie accompanied 
by oedema of the retina and lens, and later by sepaj*&yi of the vitreous 
and of the retina. When large doses are admhA’ed the lens swells 
quickly, and fluid is found between the capsut^yjd the lens-fibres, with 
degeneration of the cortical fibres. NaphtkJ^Qfttaract, when once started, 
may go on to become more dense withoi^a^i^further administration of 
the drug. Once fairly developed, it n^foir entirely clears up, but always 
leaves some opacity behind. In the wr stages crystals of phosphate of 
lime are deposited in the lens. Jl^re is oedema of the retina and lens, 
with marked proliferation of^fq^ilar epithelium and the formation of 
giant cells. Magnus 4 forfc^wiat when he gave rabbits three to four 
grammes of naphthalinjfc^j^ch kilogram of weight, the first appearances 
of cataract could be ^m^times seen after six hours. These appearances 
consisted of transpj^nt stripes in the lens, corresponding to deeper grooves 
in the lens sub|t^^. A little later peripheral cloudiness sets in in the 
anterior an(J p6%tm'ior cortical. There was marked proliferation of epi¬ 
thelium, ^iNJWe were fissures between the fibres filled with cloudy fluid. 
Accord ip ^to Magnus, the lenticular opacity thus produced may disappear 


v'Q? ^Heubel, Archiv fur die gesamfnte Physiologie, 1879, xxi., 5, S. 253. 

2 Bouchard, Recueil d’Ophtalmologie, 1887, p. 91. 

3 kolinsky, Archiv fur Ophthalmologie, xxxv., 2, S. 29. 

4 Magnus, ibidem, xxxvi., 4, S. 150. 



in eighteen days. The same author found that the use of ten to twenty 
grammes of common salt produced clouding behind the equator in four 
hours, while in a dog or in a cat one hundred grammes of grape sugar 
produced cataract, the opacities showing themselves at the equator. Hess 
agrees in the main with the foregoing statement, and describes the first 
signs of naphthalin cataract as fine, clear shoots in the equatorial parts of 
the lens, which soon become cloudy and coalesce with neighboring stripes, 
so that in ten days the entire subcapsular cortical may become evenly 
cloudy. Magnus, Kolinsky, and Hess all agree that in the early stage of 
naphthalin cataract there is great congestion of the ciliary body and pro¬ 
cesses, and it is possible that by the altered secretions of these parts the 
pabulum of the lens becomes abnormal and its nutrition impaired. Kling- 
mann, 1 also, insists that there are always symptoms of iridocyclitis before 
the slightest clouding of the lens takes place. It should be also stated that 
naphthalin usually produces a violent catarrhal diarrhoea in the animal to 
which it is administered. 

Cataract Caused by the Ingestion of Ergot.—The frequency with 
which cataracts are met in some local areas immediately after an epidemic 
of poisoning by ergot would seem to indicate that this drug has a similar 
power of disturbing the nutrition of the lens. Meyer 2 describes an epi¬ 
demic in Siebenbiirgen where the symptoms were violent cramps of the 
muscles, with consecutive contraction, anaesthesia of the feet, and, as a later 
symptom, cataract. The cataracts formed slowly, always in both eyes, and 
a large proportion occurred in young people. He attri^ntes this to spasm 
of the intra-ocular muscles. Longetsnikoff reports s^hty-one cases, and 
also attributes the formation of the opacity of th^fers to contraction of 
the intra-ocular muscles. Telpjaschin 3 saw in ^locality, one year after 
an epidemic of ergot poisoning, twenty-se^ijf?ases of cataract, most of 
them in individuals under thirty yeaitf"fc*Mge. Kortneff, after an epi¬ 
demic in the district of Nolinsk, foi^n(l^tnat cataracts thus produced re¬ 
quired from three months to onerW^r to become ripe, and that those 

_-•— fhirtyyears of age had the appearance and 

eye-grounds were pallid and the vessels 
^convulsions, but at other times there was 

occurring in individuals over t} 
consistence of senile cataract, 
contracted during the 


hbeY AND 

often hypersemia. 




ri/SQldy of some of the facts as to the nutrition of the healthy 
Jmtfie i 

A shorty- ., . 

lens wittSspible us to understand more readily the phenomena of disease. 
In pi^tSvatal existence the lens, deprived of the blood-vessels which have 


Q^ix- !• 

Ueber die Pathogenese des Naplithalinstars, Archiv fur path. Anat. 

1 M. Ignaz Meyer, Archiv fur Ophthalmologie, viii., 2, S. 120. 

3 Telpjaschin, Medizinisknop Ohorrense, xxxi., 5, S. 525. • Quoted hy Schoen. 



nourished it in the foetal state, depends for its maintenance and growth 
entirely on the absorption of fluid from the surrounding parts. It is evi¬ 
dent that the lens, owing to its anatomical build, with prismoid and band¬ 
like fibres lying in close juxtaposition, would act like so many thin glass 
plates in sucking up a capillary layer of fluid from any surrounding fluid 
medium. These being all enclosed by an animal membrane,—the capsule 
of the lens,—we would have acting the ordinary laws of osmosis, and the 
amount of fluid taken up or given out would vary with the density of the 
fluids within and without the membrane, and the amount and kind of 
matter appropriated would, as in other tissue, depend on the vital activity 
of the cells composing it. The experiments of Deutschmann 1 have shed 
much light on this process and the channels in which nutritive materials in 
the lens are most readily taken up and transmitted through its structure. 
He administered fifteen grammes of potassium iodide to a rabbit, killed it 
after three hours, and found that when the lens, enclosed in its capsule, was 
laid in a solution of platinum chloride the ensuing reaction showed that the 
subcapsular capillary layer of fluid beneath the posterior capsule and the 
adjoining layers of the posterior cortical, as well as the entire equator of 
the lens, were the parts most strongly impregnated with the iodide. The 
subcapsular layer of the anterior capsule showed the same reaction in a 
less degree, while the anterior cortical and the nucleus did not exhibit any 
traces of it. He further found that when salt was placed under the skin 
of the back in frogs the resulting cataract commenced in the equator. 
Other investigators have since attained somewhat differe^rtesults, but all 
agree that the points of most ready absorption are in <2r quatorial region 
of the lens. Thus, Ulrich, 2 using the ferrocyanido^vpotash and tincture 
of the chloride of iron as his staining material. /$2>id only find proofs of 
its absorption at the equator of the lens. /S^oler and Uhthoff, 3 using 
fluorescin, insist that the fluid enters onl/B\1me route of the zone of Zinn 
and the canal of Petit through the tfaua*Mr, and that fluid never passes 
directly from the vitreous to the lens According to Magnus, 4 vesuvin 
injected into the carotids appear^imThe eye, finding its way along the 
zonula and entering the lens ^feyfire equator. Samelsohn, 5 after study of 
the distribution of fine pai$tifl?^W iron rust in lenses in which splinters of 
iron had for some time b^^embedded, concludes that the nutrient stream 
enters the lens at tk£* abator, curves through it centripetally, collecting 
again near the anterior pole to be eliminated in the region where the 
anterior fibres t^Qjke zonula are inserted into the capsule. The exact 

method of e,—-c- 1 — 1 - 11 — J ~ - i 


i^of fluid from the lens is less well made out. Scholer and 
ir paper on the effect of fluorescin, absolutely deny that any 

1 1 Deutschmann, Archiv fur Ophthalmologie, xxv. 2, S. 227. 

Ulrich, ibidem, xxvi., 3, S. 33-82. 

^ Scholer and Uhthoff, Jahreshericht der Scholerischen Klinik, 1881. 

V 4 Magnus, Deutsche med. Wochenschrift, Nr. 40, 1881. 

5 Samelsohn, Klinische Monatsbliitter fur Augenheilkunde, 1881, S. 265. 



coloring matter ever escapes through the posterior capsule into the vitreous. 
Morano claims to have demonstrated pores in the anterior capsule, but 
their occurrence has not been confirmed by other observers. Becker, who 
worked for years at the anatomy of the lens with indefatigable industry, 
states that he has looked for them in great numbers of thin sections, but 
has always failed to find them. It is possible that further investigation 
may show channels of escape along the insertion of the zonular fibres. 
H. Bence Jones 1 has made an admirable study of the rate of absorption 
of crystalloids in healthy and in cataractous lenses. He found that where 
three grains of lithium chloride were introduced into the stomach of a 
young pig, in half an hour lithium could be demonstrated in the lens, 
while in an old pig, after the lapse of a similar interval, none was to be 
found in the lens, thus demonstrating the more rapid absorption in the 
young. He further showed that absorption took place in old, and even in 
cataractous lenses, although more slowly, and that the drug was afterwards 
slowly eliminated. Thus, when twenty grains of lithium carbonate were 
administered to a cataract patient twenty-five minutes before operation, no 
trace of lithium could be demonstrated in the lens, while in other cases 
where the same quantity was ingested two and a half hours before opera¬ 
tion lithium could be demonstrated in the watery extract of the lens. If 
three and a half, four, five, or seven hours were allowed to elapse between 
ingestion of the drug and extraction of the cataract, lithium could be 
readily demonstrated in every particle of the lens, while if a period of 
seven days was allowed to elapse, it had been entirely eliuqjVited, and not 
a trace was demonstrable in the cataractous lens when e^i^telfl. 

The equatorial region, where nutrition in the lensj^^iost active, is also 
the place where disturbances in the nutritive process* nrst manifest them¬ 
selves. vO 


Foerster 2 was the first to give an accu^t^dCscription of these changes 
by examining with moderate magnifying power the lenses of seventy-two 
eyes with commencing cataract in indiwJuals between fifty-four and eighty- 
seven years. The lenses were ohd^?d after death and placed in hollowed 
glass slides and watcli-glasseswfcJ)ersed in vitreous humor, and closed in 
with a thin cover-glass. I&gpimd the opacities forming a thin layer over 
the comparatively clear^ai^^ellow nucleus and extending as a narrow zone 
around and on both sS^g^of the equator of the nucleus. There were four 
principal forms of (Sgacity : “ first, short and narrow white lines, which 
formed a broken^J^le around the nucleus ; second, thin white clouds, which 
either exteqdjfrdin one side of the equator to the other or appear in detached 
masses oflspabn side; third, white stripes which run in a meridional direc¬ 
tion cloSe to the nucleus, and are broadest and thickest at the equator of the 

v ^^ies, Proceedings Royal Society of London, vol. xiv. pp. 

nfoSjieport, 1865, p. 221. 

& ‘ 2 Foerster, Archiv fur Ophthalmologie, iii., 2, S. 187, 198. 

400-424; also Prelimi- 



nucleus, becoming pointed towards the pole; fourth, cloudy, indeterminate 
forms which encircle the whole nucleus. The concentric clouds increase, 

and invade the entire thickness of the cortical as well as the superficial 
layers of the nucleus, but it is especially the striped opacities which increase 

in number and strength until they destroy the entire cortical.” Out of the 

entire number of lenses thus examined there was but one witli a purely 

perinuclear opacity, and it was taken from a myopic eye with a visual 
axis of twenty-nine millimetres. Foerster calls attention to the similarity 
in position of the perinuclear opacities of commencing senile cataract to 
that occupied by the stationary ones of zonular cataract. The stage of 

cataract thus accurately pictured by him is a considerably later one than 

that in which the ophthalmoscope shows us the first signs of opacity in 
the equator of the lens, and the fact that in some instances in the earliest 
stages we can alternately make the conical opacities there found appear, 
by varying the direction of the light, either dark or translucent, shows that 
we have to do with a phenomenon of total reflection, and that such appear¬ 
ance may therefore be due to spaces filled with fluid of a different index of 
refraction from the lens-fibres. Where the clouding of the lens is spread¬ 
ing throughout the cortical we have an increase in the size of the lens and 
of its watery contents, and the anterior chamber becomes smaller. This 
is clinically recognized as the stage of swelling, and the increase of size 
is supposed by Becker to be due exclusively to shrinking of the fibres 
and accumulation of fluid between them. I am inclined to believe with 
Knies, that in commencing cataract there is a molecular/gribiulation with 
increase of size in each individual fibre, but my gMmogical material 
having been derived largely from lenses obtained l^^vTraction, most of my 

that similar ones, le^ikglze, may be met with in the healthy lenses of the 
young, the only distmoMon being that the molecular contents in youth stain 
vividly, while t^C^aractous lenses these masses are less stained than the 
surrounding l^j-ftbres. This distinction can scarcely be relied on as a 
criterion^^CSmany sections of well-marked cataract such molecular ma¬ 
terial e*ramnnuch more intensely than the surrounding lens-fibres. 

fVery one, I imagine, who has examined many cataractous lenses has 
seen such appearances. The molecular degeneration of the lens- 
*fibrcs is their first microscopic evidence of cataractous change, and occurs 
very various degrees in different zones on the same lens. In seuile cata- 



ract (Fig. 29) the lens-fibres near the capsule are usually the last to present 
any considerable degree of change, while those lying between these and the 
nucleus exhibit far more advanced degeneration, while in cataract due to 
intraocular tumors and to effusion of plastic lymph on the anterior capsule 
the molecular degeneration is apt to commence close to the capsule (vide 
Fig. 59, p. 312). The formation of spindle-shaped spaces between the 
fibres is beautifully shown in Fig. 30, where the granular contents of the 
spaces have stained much more deeply than the surrounding material, have 
pushed the adjacent lens-fibres aside, and caused them to assume a wavy 
and undulating course. The cavities in this instance are most numerous in 
the perinuclear cortical. The fibres themselves are everywhere granular 
(vide Fig. 29), and the edge of the fibre seen in section often appears as 
if made up of minute beads or globules, while the granulation in the interior 
of the fibre is usually finer, and the tumescent and degenerating lens mate¬ 
rial causes the fibres to exhibit in section irregular swellings. In places 
these appear to have nuclei and resemble large vesicular cells (vide Figs. 29, 
32, and 33). The internal structure of the fibre is often fissured bv lines 
which run across it, causing it to appear as if it was broken up into irreg¬ 
ular-sized segments. Fig. 31 shows this as seen by an immersion-lens, and 
Fig. 32 represents a similar state of affairs seen under low power. 

Much less advanced changes are shown in Fig. 33. This section ex¬ 
hibits moderate molecular changes in the lens near the vortex, and the fan¬ 
shaped extremities of the fibres have been pushed from their insertion in 
the capsule by proliferating epithelium. The deeper-lying\ayers are much 
more opaque and granular, and in some of the deepaG^iirg fibres nuclei 
may be seen. Foerster claims to have demonstrateAGiight changes in the 
nucleus of cataractous lenses. Becker maintmtiOfehat the nucleus is not 
involved in such cases, but remains clear. specimens, which are 

thin sections made with microtome fronyj^ke^ imbedded in celloidin, show 
slight molecular and granular degenera^o^ with occasional dots of highly 
refracting material. Among the ern^r changes in the concentric cortical 
lens-fibres may be mentioned a stated*# hyaline degeneration, which I have 
encountered only in lenses in there has been posterior synechia, or in 

eyes with increased pressing, ar^l in which degeneration is most marked 
immediately under the^yechia. Fig. 34 represents this change in the 
external layers imnydi^Iy under the capsule. The lens is partly cataract¬ 
ous, and was found eye which was in a state of glaucoma produced by 
a sarcomatous of the chorioid. In this instance the hyaline changes 

which are coiffija1 to the external layers may possibly have been due to 
pressurewvCmhe peripheral layers of the concentric lens fibres we often 
find lar|^^findle-shaped swellings of the lens-fibres, each with a nucleus, 
sometimes elliptical, as in the healthy lens-fibre, and sometimes rounded. 
^f?Y% v ellings, when large, look like vesicular cells. Besides these forma- 
i^ioKs, and often near to them, we find large interfibrillar spaces filled with 
>Mn albuminous material, which is divided by transverse fissures, and which 

Fig. 31. 

Cataractous degeneration of lens-fibres. (Photographed by Dr. George W. Norris.) 

Cataractous degeneration of lens-fibres. (Photographed by Dr. George W. Norris.) 

Fig. 82. 


Proliferation of capsular epithelium in an over-ripe cataract. 

(Photographed by Dr. James Wallace.) 

Fig. 37. 



have been aptly likened by Becker to the appearance of the jointed algae. 
In his anatomy of the healthy and diseased lens he has most accurately 
described and beautifully figured 

as is seen m 

Fig. 35. 

Nucleated and swollen lens-fibres, “alga-like” forma¬ 
tions in the interfibrillar spaces. (Becker.) 

these appearances, 

Fig. 35—a reproduction of one of 
the plates in his work. Fig. 36, 
from a photomicrograph of one of 
my own preparations (Dougherty), 
exhibits large spindle shaped spaces 
filled with a granular mass which 
is coarsely striated in a direction 
transverse to the length of the 

Where the changes continue we 

have molecular and fatty degeneration of the cortical fibres, which event¬ 
ually break up into granular detritus, cholesterine crystals, oil globules, 
calcareous granules, and rounded albuminoid masses (the so-called Mor¬ 
gagnian balls). The molecular and fatty degeneration of the lens-fibres is 
well shown in Fig. 29. 

Fig. 37 shows the structure of one of the little white dots which form 
just beneath the capsule in over-ripe cataracts. The cells involved in it 
are evidently products of the capsular epithelium. They have, however, 
become gigantic in size, their contents are granular, and ^Aamination with 
a higher power shows that in some the nucleus is no demonstrable, 

while in others it is ill defined and breaking down. J0 In others again it 
is irregularly oval or irregularly round. Beckejp^te seen in such prolif¬ 

erating epithelial masses at times karyokinetic 
nuclei. 1 Where the degeneration of the 


and division of the 
as proceeded so far that 
the more recently formed 
fibres at the vortex degen¬ 
erate and give way, we 
frequently find that the 
proliferating capsular epi¬ 
thelium gradually pushes 
its way to the equator and 
beyond it on to the pos¬ 
terior capsule, and that 
this portion of the cap¬ 
sule is covered by a single 
or even a double layer of 
epithelial cells. Where 



the motions of the eye, usually from its greater specific gravity lying at 
the bottom of the capsular sac. Fig. 38 (after Becker, his Fig. 36, 
Tab. viii.) shows a successful section of a Morgagnian cataract enveloped 
in its capsule. The nucleus itself is undergoing degeneration, frayed 
and splitting into layers surrounded by masses of broken-down lens-fibres 
and detritus. At the equator of the lens are large masses of proliferating 
capsular epithelium. 

The chemical changes in cataractous lenses and in the nutrient fluids 
surrounding them, which correspond with the loss of transparency of the 
fibres, and which precede and accompany their degeneration and breaking 
down, have been but little studied. E. v. Jaeger 1 tapped the anterior cham¬ 
ber of normal and of cataractous eyes and had the fluid so obtained anal¬ 
yzed by Kletzinsky, and found that the aqueous of cataractous eyes was 
richer in albumin than that of normal ones. Leber 2 reports that examina¬ 
tion of the aqueous in a diabetic patient not only demonstrated the presence 
of sugar, but also a large quantity of albumin. Deutschmann 3 asserts that 
during the maturation of cataract the aqueous contains more albumin than 
does that of normal eyes. I have been unable to find any analyses of the 
human vitreous. Deutschmann found by careful drying and weighing that 
the non-cataractous senile lens becomes steadily heavier with age, and that 
the absolute amount of water diminishes while that of the solids increases. 
Priestley Smith 4 has proved that the cataractous senile lenses are smaller 
and weigh less than do healthy lenses at the same time of life, while Becker 5 
claims that senile cataractous lenses contain very considerably more water 
than do unclouded senile lenses. As to the composition ^xh5 cataractous 
lens itself, Calm 6 found, using as material lenses extr^^^by Laqueur, that 
in them the quantity of albuminous material solubltQto water and carbonic 
acid was diminished, and concludes that durif^jx]/fe a part of the albu¬ 
minous material has become insoluble. found lecithin in such 

lenses in quantity above normal. AccordiV^^/to*Jacobsen (as reported by 
Zehender and Matthiessen) 7 cholesterh^^vhich appears to exist in small 
quantities in young and normal lense!$-was much more abundant in senile 
lenses, and still more so in senikX^ftaractous ones, and that in cataracts 
there was three times as mudnJfe^tlie nucleus as existed in the cortical 
substance. He attributes l^yjH’esence to the breaking down of albu¬ 
minous material in the* and clinical observation, which at times 
shows us cliolesterin ciyt&fcals ir 

in degenerating lenses, lends strength to his 



1 Von Jaegp^S^fgfellungen des dioptrischen Apparats, S. 139-148, Wien, 1861. 

2 Leber, Ophthalmologie, xxi., 3, S. 327. 

3 DeutscN^jHn, ibidem, xxv., 2, S. 214. 

4 Priestfley Smith, loco citato, vide p. 45. 

Anatomie der gesunden und kranken Linse, S. 98. 

V'Calm, Zur physiol, und pathol. Chemie des Auges, Strassburg, 1881. 

^J^ehender and Matthiessen, Klinische Monatsblatter fur Augenheilkunde, xv., 




Besides those forms which have been already discussed as part of the 
development of senile cataract, we have proliferation of the capsular cells 
to a great extent whenever there is an extensive inflammatory adhesion of 
the iris to the anterior capsule, and at times sufficient disturbance of the 
nutrition of the underlying lens-fibres to cause either partial or total cata¬ 
ract. These changes may be congenital, and caused either from persistent 
pupillary membrane remaining adherent to the anterior capsule or by in¬ 
flammatory exudation during the foetal state. Capsular cataract may also 
occur from similar inflammatory adhesions of the iris, occurring at any time 
after birth. The accompanying figures (Figs. 39 and 40) show a partial 

Fig. 39. 

Fig. 40. 

capsular and lenticular cataract caused by retajjfccK pupillary membrane 
which was adherent to the anterior capsule. ratient was a young girl, 

aged sixteen, who thought that her sight^stfQ^ak and came for glasses. 
Vision in the right eye was normal, i il tlfc^jlfr 5/15, and with this eye she 
could read 0.50 type from twelve tcL^Wenty-eight centimetres only, while 
with the normal fellow-eye the rang^/for the same type was from ten to 
fifty-eight centimetres. Both hypermetropic, and there were no 

coarse changes in the eye-gro*mVl^ Fig. 40 shows the pupillary membrane 
and opacity as seen by tltfc^jffror, and Fig. 39 as seen by oblique light. 
Careful examination ^hd^d that the opacity extended for some distance 
into the lens-fibres, xijiiough there was a strong reflex from the lens, there 
were no other opqxCJres. Fig. 41 (copy of Fig. 1, Taf. xi., Becker’s Atlas) 
shows a partial^pract caused by a granuloma of the iris and consequent 
adhesions bdjwNen the iris and capsule. There is new-formed fibrous tissue 
betweeniA^Jh’s and anterior capsule. The latter is raised in folds, and at 
the emjato^ there is a mass of large vesicular lens-cells. Fig. 42 (Becker, 
Ta^Q^, Fig. 63) shows the appearance of the lens in a complicate cata- 
^*t from the buphthalmic eye of a seven-year-old child. A false mem- 
ne fills the pupil and binds the iris to the capsule of the lens. The an- 

Fig. 43, 

Marked epithelial proliferation in intact capsule. (Photographed by Dr. George W. Norris.) 

Marked epithelial proliferation in intact capsule. 

Fig. 44. 

(Photographed by Dr. George W. Norris.) 



terior capsule is folded and runs in ridges across the pupillary space. Be¬ 
neath it is a very large capsular cataract which is covered by a thin layer of 
capsule with epithelial cells. Behind the capsular cataract lie the lens-fibres, 
pressed and pushed away from it by an amorphous mass of exudation and 
degenerative products, while the posterior capsule is covered with a layer 
of epithelium. Subcapsular epithelial proliferation is usually marked 
wherever there is a separation of the capsule from the lens-fibres. The 
accompanying photograph gives a good picture of such proliferation in a 
lens with absolutely intact capsule, which escaped spontaneously into the 
conjunctival sac through an ulcer of the cornea, caused by purulent oph¬ 
thalmia in an infant. Fig. 43 shows a portion of the capsule everywhere 
covered with a many-layered epithelium. From one corner of the prepa¬ 
ration an irregular mound of epithelium projects inward, one side of it 
rising almost perpendicularly from the capsule to a rounded summit and 
thence sloping down gradually on the other side to the capsular level. The 
cells in the centre of the mass are smaller and exhibit an irregularly con¬ 
centric arrangement, while those of the outer layer are large and vesicular. 
The outer border of the lens is separated from the capsule by fluid, and the 
peripheral lens-fibres are irregularly swollen and are separated in places by 
spindle-shaped spaces filled with granular detritus, while along their outer 
border stretches a conical mass of vesicular nucleated cells, many layered 
near the capsule, and dwindling in thickness to a single layer as it recedes 
from it. Fig. 44 shows the same mound of epithelium more highly mag¬ 
nified, and in it we can see that the older cells at the capsular level have 
become spindle-shaped and fibroid in character. VXj 


The form and appearance of this variety o^fl^ract have already been 
described under the head of clinical appearqflft^, and reference has been 
made to the classic observation of Arlt d^^p&rating its origin. In fact, 
the subsequent observations of Knies Sdiave shown that contact for a few 
days between the capsule and the edg 0)i a perforating corneal ulcer may 
suffice to give rise to it. The l^^p examined by this author which had 
escaped from the ulcerated corm^^ r ere apparently perfectly clear, but after 
hardening, an opaque spot^J^visible beneath the capsule at the anterior 
pole, consisting of spffid^yhaped cells which gradually passed into the 
surrounding normal c|psliTar epithelium. E. Treacher Collins 2 has given 
a considerable nymfoer of admirable representations of this form of cata-* 
ract, two of whis^Tre herewith reproduced. One shows a flat form with 
the anterior* folded over it, the capsule splitting at the edge of the 

growth, ^M^trt of it with the epithelium being continued over its pos¬ 
terior surface, which is in contact with the lens-fibres. The other shows a 

1 Knies, Klinische Montsbl fur Augenheilkunde, 18-181. 

3 Collins, Trans. Opkthal. Soc. U. K., vol. xii. pp. 89-102. 





Slight separation of the capsule at the equator of the lens and folds in 
the anterior capsule may occur from many causes besides that just described 
under the head of capsular cataract. Topolanski 1 has called our attention 
to the fact that in some cases of congenital coloboma of the lens the capsule 
passes over the notch in the same circular line as the capsule elsewhere, 
leaving a considerable clear and fluid-filled space between itself and the 
lens. The same fact has been noted by Christen. Topolanski and also 
Magnus tell us that at times tent-like elevations of the capsule can be seen 
in perfectly healthy young lenses, due to the drag of the zonula. Ac¬ 
cording to Schoen all simple or senile cataracts commence as a “ peripheral 
capsulitis” and have their starting-point in the separation of the lens-fibres 
from the capsule at the points where the zone of Zinn is inserted into them. 
He considers that this state of affairs is caused by strain of the accommo¬ 
dation after the lens has become hard and unyielding, and thinks that 
similar small detachments of the capsule are caused in the young by the 
effort to overcome hypermetropia and astigmatism. The initial lesions of 
cataract according to this author are the separation of the lens-fibres from 
the capsule and the proliferation of the epithelial cells, which is often 
followed by a hyaline degeneration and a coagulation necrosis of the cells. 
Topolanski considers separations of the equatorial capsule (demonstrated 
through the coloboma of a preliminary iridectomy) to be frequent in all 
senile cataracts. This author and also Sattler and Inotaye consider such 
separations common in cases of over-ripe cataract with capsular degener¬ 
ation. Folds in the pupillary space may be seen o^pbnally after wounds 
of the eye both penetrating and non-penetratingTy^opolanski has observed 
them caused by the contraction of effused ly^ ii0> Inder a posterior synechia 
after iridectomy, in which case the pull qf'ys cicatrix also made a slight 
indentation in the periphery of the l^s^^fhe folds were few in number 
when first observed with the oplitll^lmoscope, but became more numerous 
from day to day till fourteen wedQ^unted. When the eye was examined 
with a weak-light mirror sligj^rotations of the latter caused remarkable 
changes in the appearance DQhe more or less spindle-shaped elevations of 
the capsule. With a s&raut projection of the light they looked dark, and 
then by slight motmpfoVtne mirror lighted up brilliantly like illuminated 
glass splinters. I^ou^e 2 also gives an interesting instance of capsular folds 
in the pupillary^ttace in a case of double traumatic iridodialysis. In this 
case the foldjpiran across the pupillary space in a direction at right angles to 
the direetitfJVtfi the blow producing the injury; while in the spaces above 
and WO^vbetween the periphery of the detached iris and the cornea, the 
edga omhe lens could be seen and was found to be markedly serrated. No 
f cnpsule or zonula was visible at these points. Larger detachments 

1 Topolanski, Klin. Monatsbl., Maerz, 1897; also Archiv fur Ophthal , xli., 3, S. 198. 

2 T. Inouye, Centralblatt fur Augenheilkunde, Mai, 1897, S. 147. 

. • iVf\ 


Fig. 48. 

traumatic cataract; m process ol absorption 

(Photographed by Dr. James Wallace.) 



are seen in many cases where the fluid rapidly accumulates under the cap¬ 
sule, as in the case of diabetic cataract figured by Becker and in the case 
of the lens of a suppurating eye shown in Fig. 43 and described on page 
303. In both these cases there were remarkable ingrowths of the capsular 
epithelium. In many other instances in over-ripe and Morgagnian cata¬ 
racts there are considerable spaces between the capsule and the lens, but 
these, although also separations, are due mainly to shrinking and degener¬ 
ation of the lens-substance with subsequent dissolving and osmosis of the 
degenerated material rather than to any pull or raising of the capsule. 


1. Without Rupture of the Capsule.—Berlin has succeeded in pro¬ 
ducing cataract by repeated blows on the cornea with an elastic rod. 
Voelckers 1 has since confirmed these results by producing cataract by 
tapping an eye with a percussion-hammer or shooting it with projectiles 
from a toy pistol. Schirmer has shown that contusions of the lens-capsule 
either cause more active absorption of fluid by the lens or interfere with the 
excretion of its nutrient fluid, producing an accumulation of liquid between 
the lens-fibres which pushes them apart. It, moreover, causes granular de¬ 
generation of all the fibres with a proliferation of the epithelial cells form¬ 
ing ingrowing masses of tissue, which Schirmer believes to remain trans¬ 
parent and not to give rise to opacities. Clinically, also, we are familiar 
with cataracts coming on at varying periods after blows on the eye and its 
vicinity where we are unable to demonstrate any rupture of tta\apsule. 

2. With Rupture of the Capsule.—As will be shownrojbhenext sec¬ 

tion, there is good clinical evidence of the healing of smaiWd^psular wounds 
so as to leave no trace of their previous existence. Agt©*ding to Schirmer 2 
in such instances a fibrous cap is formed by exudd^&jj/ and this formation 
is followed by a proliferation of the capsular opM(je)ium, the cells thus pro¬ 
duced secreting a vitreous membrane, whicl^ljjbvks forward between the 
old capsule and the epithelial layer to coyer in the defect. Hoering, 3 who 
experimented on wounds in the anterior capsule in animals, says that such 
wounds always tend to unite by simd^adhesion, and that failure to do so 
is usually due to swelling of the kpa^bres. He maintains that the wound 
always unites if it be made b^^Srarp instrument, and if it be confined to 
the capsule without injurytQhe lens-fibres. The small, irregular masses 
of lens-matter which prok^je through wounds in the capsule soon become 
opaque from the actiothe aqueous and disintegrate, and are dissolved 
by the further acti^Twthe same fluid. Fig. 48 shows a section of a trau¬ 
matic cataract the wound has been large and has eventuated in the 

absorption G^o^>bulk of the lens in the equatorial region. We see broken 
lens-fibresgrayed at the edges, and between them quantities of irregularly 


. -, quoted by Schirmer, Archiv fur Ophthalmologie, xxxiv., 1, S 

ASchirmer, ibidem, xxxv., 3, S. 220. 
loMIoerinff, Ueber den Sitz und die N 

133 . 

ioering, Ueber den Sitz und die Natur des grauen Staars, Heilbronn, 1844. 



round, albuminoid masses without nuclei,—the so-called Morgagnian balls, 
which are simply the degenerating protoplasm of the fibres. The masses 
of lens-matter which lie nearest the equator and farther from the wound are 
best preserved, while those nearer the centre of the photograph, which are 
closer to the wound and have been more thoroughly exposed to the action 
of the aqueous, are in a more advanced stage of degeneration, the lens-fibres 
exhibiting numerous fine transverse striae and molecular degeneration. Be¬ 
sides the changes above described and pictured, one often finds, as in Fig. 
49, which represents another field and a more highly magnified portion of 
the same lens, curious forms of degeneration, which are seen in the interior 
of lens-fibres and which themselves still are comparatively intact and pre¬ 
serve their band-like outline. These consist in the formation of large round 
or ovoid excavations in the fibres, the edges of which are usually sharp cut 
and which are filled with protoplasmic masses, which are at times nucleated, 
and which sometimes entirely fill the cavity, or at other times have shrunken 
away from its walls. These rounded masses often communicate, by pro¬ 
longations of granular material in the rents in the fibres and in the inter- 
fibrillar spaces, with similar masses lying in adjacent cavities. In other 
instances no appearances resembling nuclei or cells are to be found, but 
simply clumps of degenerating material. Fig. 50 gives a view of a large 
part of the shrunken capsular sac in a case of traumatic cataract. Part of 
the iris is shown in the upper right-hand corner of the picture; between it 
and the rent in the anterior capsule is seen a mass of inflammatory exudate, 
partly pigmented. In the interior of the capsular sac lies^i small piece of 
lens-matter broken into fibrils with frayed ends, wlii^^r^ surrounded by 
a mass consisting of leucocytes, Morgagnian balls, an^^ns-detritus. It has 
been frequently observed that in traumatic cataractf^mnt cells are found con¬ 
taining myelin drops and broken-down lens^n^in\ Lately Wagenmann 1 
lias called special attention to them, ascrilrfreVto them marked histolytic 
action, and in one case of spontaneous )n of the lens consequent on 

iridocyclitis he imputes to these cell^n ability to cause absorption of the 
vitreous capsular material and usurtQ^ the capsule. At times we have also 
a form of degeneration of the len(0|bres, in which they break up into narrow 
transverse bands, the lines ofJ©teion being so close as to recall the striation 
of muscular tissue. As^hiCfarrow bands loosen and fall off they become 
rounded and break m nailer rounded masses, (vide Fig. 51). Wounds 

of the lens-substanc^jlirough the anterior capsule make a gray track, by 
which we can ibjjswv their course, and often the only other opacity in ad¬ 
dition to this mV De radiating opacities in the posterior cortical. Leber 
informs us when he removed a piece of the anterior capsule of the rabbit 
he obta^^Wfc nuclear cataract. When the entire lens is absorbed, the anterior 
and ptostehor capsule may fold together, stretching across the eye behind the 
pt»0^ the level of the insertion of the zone of Zinn and resembling the 

1 ‘Wagenmann, Arcbiv fur Ophtlialmologie, xlii., 2, S. 30. 

Fig. 50. 

em m. % 



secondary cataract resulting from cataract operations. In most instances 
such complete absorption does not occur, and we have a shrunken lens of 
irregular shape sitting just behind the pupillary space and often bound by 
inflammatory adhesions to the cornea or the iris and ciliary body. Violent 
iridocyclitis, often followed by detachment of the retina and vitreous, or 
by sympathetic affections of the fellow-eye, only too frequently results. 

Of late years a considerable number of cases of traumatic cataract 
caused by lightning have been recorded, and consequently the experiments 
of Hess, who produced it by discharges from a Leyden jar, become inter¬ 
esting. The discharges produce contraction of the pupil, chemosis of the 
conjunctiva of the eyeball, circumscript cloudiness of the cornea, intense 
hypersemia of the ciliary body, and clouding of the lens. The opacity of 
the lens commenced near the equator, then followed clouding of the epi¬ 
thelial cells of the anterior capsule and anterior cortical cataract. Hess 1 
likens it to the effect of massage on the lens, and states that in both there is 
death of the epithelial cells. Si lex has reported the case of a child three 
and a half years old, who was struck by lightning and who remained in¬ 
sensible for five hours. There was no visible wound of the eyes, but both 
eyes presented pericorneal haze and injection, with corneal and lenticular 
haze. Eleven months later these conditions had very much diminished but 
had not entirely disappeared. Leber has collected eighteen cases of injuries 
of the eyes by lightning. In nine of these cataract formed (exclusive of a 
tenth case, that of Vossius, where the cataract was due to cksAoiditis). The 
remaining cases displayed the most varied pathologicai^^dixions, such as 
optic neuritis, hemorrhages at the macula, rupture chorioid, detach¬ 

ment of the retina, paralysis of the external rjCi^cIes, opacities of the 
cornea, and intolerance of light. ^ . 

In some instances of traumatic catarac^^^ompanied with partial dis¬ 
placement of the lens, the iris is either ^us^ea back or retroflected at the 
junction of the circular and radiatiugXbres and partially or entirely disap¬ 
pears from view. The well-known %^e of von Ammon, 2 where a concus¬ 
sion of the eye was produced H0Jie discharge of a musket loaded with 
water against the roof of thejjQWh, is an example of this; while Treacher 
Collins reports two cases^^partially-displaced cataract which were accom¬ 
panied with rupture of tfft^nbres of the ligamentum pectinatum going to 
the iris, and by a sp^t iythe ciliary body which separated its circular from 
its longitudinal fibres^ 

traumatic c&t^ract produced by the operation of discission. 

The, f^TOwung photographs show the effect of a careful tentative discis¬ 
sion ofN^i lens in an adult of thirty years of age, where, owing to the 
smaj j^mount of resulting absorption, the lens was subsequently extracted. 

Hess, Experimentelles ueber Blitz-Kataract, Bericbt der VII. internat. opth. Kon- 
ijpess, Heidelberg, 1888. 

J 2 Von Ammon, Archiv fur Ophthalmologie, i , 2, S. 119. 



Fig. 52 shows how the lens-tissue has been cut and torn by the lever-like 
motion of the discission needle, breaking up the lens-fibres into irregular 
band-like portions with serrated edges at the fracture, and separating groups 
of fibres, leaving between them spaces filled with granular debris and irreg¬ 
ular globules of breaking-down lens-substance. On each side of the cap¬ 
sular rent caused by the entering needle there are evidences of active efforts 
at repair in the epithelial cells, which have become much enlarged with dis¬ 
tinct nuclei and granular contents and are in active proliferation. Fig. 53 
shows in a field a short distance from the first how between some of the 
fibres there are spindle-shaped interstices, in which lie masses of degener¬ 
ating lens-material, each mass broken up into cylindroid clumps with well- 
marked lines of division at right angles to the genetal direction of the 
spindles. In this instance (Fig. 54) two perforations of the capsule have 
been made by the needle, lying near to each other. In one of these a band¬ 
like mass of lens-fibres fills the opening and protrudes from it. It is 
frayed and expanded at its outer end, from the action of the aqueous, and is 
commencing to be covered by a fine layer of fibrinous material. The adja¬ 
cent opening, which is smaller, has been more completely closed by a heavier 
layer of similar fibrinous material, as is well shown in Fig. 55, where the 
nature and extent of the fibrinous exudation which covers the torn ends of 
the capsule, the breaking-down of the lens tissue, and the large nucleated 
cells formed by the epithelium are plainly visible. Examination of the 
fibrinous cap with an immersion-lens shows still more distinctly that its 
outer side is composed of a very delicate layer of minate\spindle-shaped 
cells with small bodies and long fibre-like processespalF closely felted to¬ 
gether. The healing of wounds of the capsule^Vrrlight be expected, is 
closely analogous to the healing of wounds in J^^membrane of Descemet, 
where Wagenmann 1 and subsequently Gem&C'liave shown that the cut 
ends never reunite, but are covered in l/f~'fik^us material beneath which a 
new vitreous membrane is formed kft the^ndothelial cells. Implantation 
cysts of the iris and ciliary body a^Smetimes found after traumatic cata¬ 
ract and at times after operationA>rT5ataract. The cyst is lined by a lami¬ 
nated epithelium, probably from some of the corneal or conjunc¬ 

tival epithelium which ]ms(0^5^airried into the wound. In some cases of 
traumatic cataract we fi^cilia in the anterior chamber which have been 
carried in by the ii^Frdwent causing the wound. 

Cap of fibrinous and spindle cells covering the wound made by a discission needle. 

(Photographed by Dr. George W. Norris.) 

Two perforations in a lens from a discission operation. (Photographed by Dr. George W. Norri-s.) 

Fig. 55. 



lens-matter which sticks in the equatorial region. The anterior capsule 
retracts in folds, and applies itself against the posterior capsule, and, adhe¬ 
sion taking place, the lens matter lefc behind in the periphery of the capsu¬ 
lar sac is shielded from the absorbing action of the aqueous. The capsular 
epithelium proliferates and produces a transparent mass of vesicular epithe¬ 
lial cells and of abortive lens-fibres which push their way into and around 
the more or less opaque cortical remnant. The general appearance of such 
a mass is well shown in Fig. 56. In the young this reproduction of lens- 
fibres is considerable, and distends the equatorial part of the capsular sac, 
imaking a thick ring around the pupil, its position corresponding nearly 
with the insertion of the zone of Zinn. In young animals where the lens 
has been removed experimentally, the mass of clear fibres reproduced is so 
great as to cause Milliot and others to speak of regeneration of the crys¬ 
talline lens. V. Collucci, 1 Wolff, 2 and later E. Mueller 3 have shown that 
after extraction of a lens in triton larvae there occurs a seemingly com¬ 
plete regeneration of it, not by means of any proliferation of capsular epi¬ 
thelium, nor from any ingrowth from the horny layer of ectoderm, but by 
a growth on the posterior layer of the double layer of epithelium on the 
iris (pars iridica retinae), the cells of which, after losing their coloring ma¬ 
terial, proliferate and form concentric layers, eventuating in a closed sac with 
transparent fibres resembling in size and appearance those of the original 

Where proliferation fills the periphery of the capsular sac and stops at 
this point, while the pupillary capsule remains clear, we have the normal 
state of affairs, but in the vast majority of in¬ 
stances we have at various periods after the 
operation of extraction a clouding of the pupil¬ 
lary capsule, which, when viewed by obliqu(j 
light, varies in appearance from the finest spidej? 
web to a decided whitish opacity. Fi| 
gives the normal appearance of the capful^frfid 
peripherally enclosed mass after a succe^^l flap- 
operation for cataract. The exaofyshape and 
size of the rent in the capsule ai^Srery various, 
even where an attempt is ause a linear 

cut in it with a sharp inst»cmeht. It is readily 

torn by the instrumen^ajra once opened, the escaping lens often rips and 
tears it in various di^coons, so as to present very different appearances in 
different cases. shows the appearance of the capsular sac and the 

position of the>pA^s of the anterior capsule after a simple extraction. The 
rents in tfo&CWktance extend fairly out to the zonula. The preparation is 

Capsular rents after simple ex¬ 
traction. (Hasner.) 

3 in 


1 Nagel, Jabresbericbt, 1896, S. 34. 

2 Wolff, Biologisches Centralblatt, No. 17, 1894. 

* E. Mueller, Archiv fur micros. Anatomie, xlvii. S. 23. 




represented as seen from behind, the eye having been removed from a 
patient who died of endocarditis fourteen days after the operation. Thick¬ 
ening often takes place in the pupillary capsule without any definite 
assignable reason, but its occurrence is much favored by any healing of 
the capsule in the extraction wound or by any ever so slight adhesion to 
the uveal coat of the iris. The incarceration of a flap of capsule appears 
to act as an irritant, because it resists the normal contraction of the zonula, 
which even in lensless (aphakic) eyes takes place in the normal convergence 
for near work. Healing of the iris or of the hyaloid in the wound often acts 
in a similar manner and gives rise to recurrent attacks of inflammation. 
Such impalements also form an inclined plane for infectious material or in¬ 
flammatory products to pass to the pupillary region. Where blood settles 
on the capsule it leaves a fibrous coating after its absorption, while attacks 
of iritis by plastic effusion add to its density and toughness. The drag 
of the contracting plastic effusion and the effects of ciliary inflammation 
spreading to the retina and chorioid cause chains of pathological effects 
which give rise on the one hand to detachment of the retina, to chorioiditis, 
and to those forms of disease which lead to the shrinking of the eyeball to a 
sightless stump, and, on the other hand, where they pull forward the root of 
the iris and the ciliary processes so as to close the angle of the anterior 
chamber, to increase of pressure and glaucoma. 

Secondary Cataract.—Where the opacities of the lens follow and are 
evidently due to other preceding diseases of the eye, we have a variety of 
cataract which is apt to form rapidly. The frequent occurrence of cataract 
after adhesions of the iris to the lens has been alroaw discussed, but cata¬ 
ract often follows iritis, with clouding of the aon^&s^and effusion into the 
anterior chamber when no adhesions have takAC^lace. The nutritive and 
glaucomatous changes produced in eyes bwt&^rowth of intra-ocular tumors 
often also cause cataract. The accomrtaAwiig illustration (Fig. 59) repre¬ 
sents a cataractous lens taken from which during life showed a detach¬ 

ment of the retina in the lowei>outojr equatorial region, followed by a rap¬ 
idly-forming cataract which wa|Syhitish-gray in appearance. The sections 
showed a sarcomatous grou^liNmder the detached retina. There were no 
synechise or effusions of^fAwtic material into the anterior chamber. The 
opacity of the lens war^V^atest in the subcapsular and superficial layers 
of the cortical, and^^isted, as shown in the figure, of various forms of de¬ 
generation of igpi|k#lial cells, granular clouding of the lens-fibres, with 
many chinks mmee n the fibres, the larger ones being spindle shaped and 
filled witft^Jphips of degenerative material and large vesicular cells. Cat¬ 
aract isjMunon also after disease of the chorioid and of the pigment epi- 
thelmVof the retina, in the latter cases usually commencing as a posterior 
c^^^hl cataract (< e.g ., in typical pigment degeneration of the retina). 
-s^When suppuration of the chorioid occurs, and the vitreous is infiltrated 
v'Q* itli pus, the lens often becomes softened and opaque. The earlier writers 
Q* describe the appearance of pus within the capsular sac, mostly between the 


Fig. 59 


f !V\ 

■J « 6 * 


Cataract following tumor of the chorioid with, attach men f, of the retina, the greatest changes 
being near the anterior capsule. \Vh^ogmphed by Dr. George W. Norris.) 

)noid with qj 
ipsule. jFhW 

Fro. 60. 

Leucocytes between the lens-fibres in a case of traumatic cataract. 

(Photographed by Dr. George W. Norris.) 

.Fig. 61. 

k ^fJeucocytes between the lens-fibres in a case of traumatic cataract.—More highly magnified. 

(Photographed by Dr. George W. Norris.) 



lens-fibres. Thus Weber 1 remarks that he has seen pus-formation within 
the capsule in cases of artificially produced abscess of the vitreous, due to 
proliferation of the capsular epithelium, while Moers 2 is of the same opin¬ 
ion, and describes and pictures the endogenous formation of nuclei in the 
lens epithelium and fibres. Knapp, 3 in a case of metastatic chorioiditis, 
found pus in a lens with intact capsule. The anterior epithelium was 
single-layered and intact, the equatorial epithelium proliferating, and many 
of the lens-fibres swollen into a spindle form. In some, several such swell¬ 
ings were close to each other, each with a nucleus and nucleolus. Gold- 
zieher and Becker also saw pus within the capsule, but attribute its presence 
to an in-wandering of leucocytes, made possible by thinning and usure of 
the capsule, as was proved by the actual measurements made by Becker. In 
all probability most of the earlier observation of leucocytes within the cap¬ 
sule when there was no perforation or usure of this membrane were cases 
in which proliferating masses of epithelial cells had been mistaken for them. 
Figs. 60 and 61 show quantities of leucocytes in lines pushing their way in 
the cracks in the fibre-layer in a case of traumatic cataract. The leucocytes 
have evidently entered from the anterior chamber thtough the ruptured 
capsule and lie in interstices between the fibre bundles, which themselves 
show granular degeneration. On the other hand, Figs. 43 and 44 show 
masses of proliferating epithelial cells in a case of unbroken capsule, where 
the lens, freed from its zonular attachment by the inflammatory processes 
of purulent ophthalmia, floated out into the conjunctival sac through a per¬ 
forating ulcer of the cornea. The lens-fibres have been freed from their 
attachment to the capsule, and between the two is a fluid-filJM space, into 
which project irregular rounded masses of epithelial c^^viiich, where 
they are small and round, could readily be mistaken fercftucocytes. Most 
of the more recent writers deny any considerable m^meration of either the 
lens-fibres or of the capsular epithelium. Thus ff “ never saw nuclear 

division in a fully developed lens-fibre, but^^fO always convince himself 
that where there were apparently two micig^n one lens-fibre there were 
really two fibres matted together.” Deu^wmann 4 found usure of the ante¬ 
rior and posterior capsules with leumc}Ves sticking in the capsule. 



In lenses which have lch^ytteen cataractous, especially in those where 
the opacity has developed;*sequence of chorioidal disease, we often have 
granular deposits of pl^&pnate and carbonate of lime within the capsule, 
which at times, esp^dSjly in young subjects, goes on to complete calcifica¬ 
tion of the lens. teording to Stellwag 5 such deposits of lime salts are 

> Mr 




O. Weber, Virchow, Archiv, xix. S. 367. 

Moers, ibidem, xxx. S. 45. 

Knapp, Archiv fur Ophthalmologie, 1867, xiii., 1, S. 127. 

Deutschmann, ibidem, xxvi., 1, S. 135. 

5 Stellwag, Lehrbueh der Augenheilkunde, S- 668. 



sometimes in the crystalline form. Usually the infiltration commences 
immediately beneath the capsule, as in a case reported by Middleton Michel, 
where the capsule and adjoining portions were calcareous. On incision of 
this shell, the nucleus was evacuated, while the capsule and adjacent corti¬ 
cal were so stiff that they still maintained the curvature of the lens. Any 
approach to complete calcification of the lens is always a slow process and 
generally occurs in eyes which have been diseased for years. Wagner, in 
1851, was the first to report having found true bone with Haversian 
canals and bone-corpuscles in the shrunken lens of a shrunken eyeball. 
Most authors, however, doubt the possibility of bone formation from the 
cells of epithelial origin which constitute the lei s, believing that it only 
forms in fibrous tissue, and explain the occurrence of bone in this situa¬ 
tion either by rupture of the posterior capsule and the entrance of vitre¬ 
ous humor, which may in some instances carry newly formed vessels, 
or (Becker) that in shrunken eyes a vitreous formation may be pushed 
nearly into the place once occupied by the lens. Voorhies 1 describes 
true bone formation in the lens, Keyser 2 reports a case of formation of 
bone in the lens, and Alt has seen bone within the capsule in two cases, 
but thinks that it was preceded by usure of the capsule and the formation 
of fibrous tissue. 


In the preceding paragraph the occasional occurrence of crystals of the 
carbonate and of the phosphate of lime have been referred to. More com¬ 
mon, although rare, is the formation of cholesterine and tvAsine crystals in 
the lens. As previously mentioned, cholesterine is t(X|>§ round in every 
lens, in greater abundance in the lenses of the old^S&n in those of the 
young, but it is seldom that it crystallizes in demonstrable quantities in this 
organ. Crystalline deposits of it are more non in the vitreous, and 
attention was first called to them by PadidjQLandrau in 1845. Since the 
invention of the ophthalmoscope the oc(^r^m5e of synchisis scintillans has 
occasionally been seen by all ophtham^c surgeons of considerable clinical 
experience. A deposit of cholesterm^ crystals may also occur on the cor¬ 
nea, and the author has recenth^^n crystals of it thickly sprinkled on the 
membrane of Descemet and p&wb posterior layers of the cornea in a case of 

l 1 Wj 

Dr. Ring’s 3 and also in ofi^^ported by Dr. Charles A. Oliver. 4 In the lens 
the presence of chol^ te42)s crystals has several times been proved by the 
extraction of that org^jand microscopic examination of it. It may appear 
as a rarity either; early or in the last stages of cataract, although it 

is much more ffiyient in the latter. The first record of cholesterine in the 
—- 1 — 

1 Archiv fur Augen- u. Ohrenheilkunde, vii., 2, S. 311. 

2 EieysCT, Report of Fifth International Ophthalmic Congress, 1876, p. 131. 
ram Ring, Ophthalmic Section of the College of Physicians of Philadelphia, 

ry, 1898. 

4 Charles A. Oliver, ibidem, October, 1898. 




lens was probably that of Adam Schmidt/ who found it in the diseased eye 
of a peasant girl, aged twenty-five, which, on pressure, felt as soft as “an 
over-ripe fig.” In the anterior part of the cataract there was a “glittering 
red, silvery, and golden powder,” with a deposit one line deep of the same 
material at the bottom of the anterior chamber, which would disperse itself 
through the aqueous with every sudden motion of the head. On extract¬ 
ing the cataract there was an escape of aqueous, filled with glittering crys¬ 
tals, as well as of some fluid vitreous. Crystals of cholesterine may also 
occur in lenses in healthier eyes which are still sufficiently transparent to 
allow of some useful vision. Krautschneider 2 found them in the deeper 
layers of a lens in an eye with V. = 6/60. Such crystals may remain in the 
lens a long time without apparent change. Thus, Tweedy 3 saw them re¬ 
main unchanged for months and Lang for ten years. Usually, however, 
the lens in which they are deposited undergoes further degeneration, and 
they float in the d&bris within the capsular sac. Von Graefe records an in¬ 
teresting case in which the crystals were deposited in the anterior and pos¬ 
terior cortical of a still partially transparent lens, and in which he could fol¬ 
low the breaking down of these layers until the nucleus floated freely in the 
liquefied and crystal-charged material within the capsule. The author has 
encountered two marked cases of cholesterine deposit in the lens, one in a 
soft and partially atrophic eye, where the anterior cortical was filled with it, 
and in which there were also masses of crystals lying at the bottom of the 
anterior chamber. In the other, in a partially formed cataract of a negress 
of fifty years of age, who still had a vision of 5/40, there were quantities of 
cholesterine plates in and between the lens fibres of the^rfm^or and poste¬ 
rior cortical. The plates were arranged at various ang^^&nd when lighted 
up by oblique light many of them were struck at>l^polarizing angle and 
presented a most gorgeous display of prismatic ^^and green, such as one 
sees in similar crystals when laid on a slide ^T^riewed with the polarizing 
microscope, while the crystals standing ^Twr angles appeared grayish 
white. In the lens of the fellow-eye tfere were minute angular gray spots, 
probably cholesterine crystals in the ^r^ckss of formation. It is stated that 
where we have within the capsule^j a degenerated and semifluid lens such 
accumulations of phosphate ofQjue or of cholesterine, if an operation is 
attempted the lens should be extracted in its capsule, as the crystals do not 
all escape, and those Uitfgyhi the iris in either the anterior or posterior 
chamber are said to pfro\^ very irritating to the eye. 


The effectsuQyphdis on the lens are usually indirect, by affecting the 
blood-ves^sA^the eyeball or (according to Michel) the carotids without 

Jcl^nnStj Die Cataracta (aus den hinterlassenen Papieren) von J. A. Schmidt in 
etheilt von Herrn Dr. Eble in Wien, Yon Ammon’s Zeitschrift fur Ophthal- 

rautschneider, Beitrage zur Augenheilkunde, Heft xxvi. S. 34. 

Tweedy, Lancet, 1874, ii. p. 529. 



disease of the intermediate vessels. It may, however, be infiltrated by ad¬ 
jacent gummatous growths, as in the case reported by Scherl. 1 A gumma 
of the iris and ciliary body destroyed part of the anterior leaflet of the zone 
of Zinn, and a small-celled infiltration extended through Petit’s canal and 
inserted itself in many places to varying distances between the fibres of the 
lens. In a similar manner gliomatous growths may after perforation of the 
capsule push their way between the fibres and thus infiltrate the lens. 


Cataracta nigra is a name under which are included two varieties of 
cataract. In the one the lens is blood-infiltrated and blood-stained. In 
the other we have a lens where the cortical has been slowly and completely 
converted into nuclear tissue which lias itself subsequently undergone slight 
degeneration. Of the first variety von Graefe 2 gives us an instructive 
history. It occurred in the eye of a youth who had received a severe 
contusion of the globe. The cataract in situ appeared yellow-brown; the 
lens-fibres were infiltrated with brown coloring-matter, which chemical ex¬ 
amination showed to be identical with blood-coloring matter. Gillet de 
Grandmont 3 also reports a case of black cataract where the presence of 
blood-coloring material was proved by spectroscopic examination, although 
he failed to find the characteristic appearances of haematin, obtaining only 
what he characterizes as the spectrum of altered or pigmentary haematin. 
The recent experiments of Linde 4 are interesting as showing the effect of ex¬ 
tensive hemorrhages into the anterior and posterior chambers ton the entrance 
of blood-coloring matter into the lens. After such liemc^^a^s in a rabbit 
there was a deposit of fibrin on the anterior capsule wi^^ilclosed blackish- 
brown blood-crystals. The layers of the anteriq£%^d posterior cortical 
were stained reddish brown by the dissolved c^r^-matter of the blood, 
the nucleus remaining nearly free from it. MN^fcirdy 5 reports a carefully- 
examined and interesting case which hs^dly^pears to belong to either 
variety. The lens appeared as “ black^sTcfiareoal’’ in a very thick capsule. 
Spectroscopic analysis by MacMunn ^^wed that it contained no trace of 
haemoglobin, of methaemoglobin, ortaematin, and that therefore the coloring- 
matter was not derived from thQJood, but appeared to belong to the same 
class of pigments as melanin^ MAiTiro 6 has examined ten black cataracts, and 
believes that the coloring/nvfcter is always derived from the blood. In his 
cases it consisted eithefottnaematin, haematoidin, or melanin. The few cases 
which have come^nmler the author’s observation have all been examples of 
the second variefai^ne color has not been charcoal-black, but by transmitted 

1 Scherl^^Qhr fur Augenheilkunde, 1892, S 287 (German edit.). 

2 Yon^^^, Archiv fur Ophthalmologie, i., 1, S. 133. 

Giile^e Grandmont, Archives d’Ophth., May, 1893, p 279. 

e, Centralblatt fur prakt. Augenheilkunde, Juli, 1896, S. 196. 
ardy,-Trans. Ophthal. Soc. U. K., ii. 10. 

iloauro, quoted in Centralblatt fur prakt. Augenheilkunde, 1896, S. 691 ; Riforma 



light of a rich mahogany-brown. In these cases, as in those studied by 
Becker, the growth of the lens had gone on uninterruptedly until advanced 
age, when the germ or formative force of the anterior epithelium had become 
exhausted and no new fibres were formed; then those last formed, instead 
of softening and breaking down, applied themselves to the nucleus, and 
underwent the same hardening process as the earlier-formed nuclear fibres. 



It has been repeatedly demonstrated that the lens of vertebrate embryos 
and of young animals becomes cloudy after death. Kunde (1857) showed 
that frogs exposed to severe cold became cataractous, and that the lens 
cleared when by exposure to heat the animal resumed its natural condition. 
Michel has shown that this opacity is due to the formation of vast numbers 
of small, round drops with a high index of refraction in the nuclear fibres 
of the lens, and that the opacity clears up and disappears at a temperature 
of from 15° to 20° Centigrade. On cooling, the opacity again develops, 
but it can again be cleared up by raising the temperature. The same 
author has demonstrated that a great reduction of temperature in living 
animals is accompanied by the formation of cataract. Wernek showed 
that concentration of the sun’s rays by a burning-glass caused the lens to 
split in the direction of its meridians and to become opaque, while more 
recently Widmark has shown that probably other influences in concentrated 
light come into play, and that the ultra-violet rays cause a splitting of the 
lens, accompanied by marked fluorescence; and Beer, Mackenzie, 

Arlt, and Hasner, from their clinical experience, all acKPhcfc radiant heat as 
a predisposing cause of lenticular opacity. Meyh^C^y after an examina¬ 
tion of five hundred glass-blowers, found in ftftjPpne cataract in various 
stages, mostly on the side exposed to the heaWfeft side), and accompanied 
by a characteristic discoloration of the sktfnqjrtthe face on the same side. 
He attributes these appearances to th^^normous sweating and local ab¬ 
straction of water from this side of tl(^body. His statistics, however, do 
not show a very high percentage^ cataract. Taking four hundred and 
forty-two of the above cases unJ^r)Corty-two years of age, only forty-two— 
that is, 9.5 per cent.—sho\^AWLms opacities, a ratio which would appear to 
be rather below the no^jnfffv^mce Schoen, out of four thousand four hun¬ 
dred and eighty-three\ca^es under forty years of age, taken as they came 
to the Leipzig clyij^found 11 per cent, with traces of cataract. Hirsch- 
berg 2 reports tbsy*?ut of thirty glass-blowers in one factory five were 
affected with ^J^fact and had the characteristic discoloration of the skin 
of the fa^N^He holds that when an individual is long exposed to high 
heat, somiiSm is absorbed by the lens as to cause fine internal changes and 
sub^oqS^tly loss of transparency. The examination of a considerable 

Meyhoefer, Klinische Monatsblatter fur Augenheilkunde, 1886, S. 49. 
or 3 Hirschberg, Centralblatt fur Augenheilkunde, April, 1898, S. 113. 



number of cases of men who were constantly exposed to intense radiant 
heat (puddlers, stokers, glass-blowers, etc.) has convinced the author that 
such exposure, if long continued, does result in a disturbance of the nutri¬ 
tion of the eye. The ophthalmoscope shows that in men long pursuing 
such trades the head of the optic nerve is markedly over-capillary, and that 
the reflex from the chorioid is of a far more intense red than usual. The 
retinal epithelium is disturbed, and appears woolly and granular, and in a 
large proportion of such cases we find greater or less opacities in the lens. 
Yon Ammon 1 has studied the effects of heat on the eyes of persons who 
had been burned to death in an accident on the Versailles Railway. One- 
half of the body examined was almost entirely carbonized; on the other 
side, which was less burnt, the eye was removed from the socket. There 
was slight wrinkling of the sclerotic and of the upper part of the cornea. 
The retina was detached, the vitreous shrunken, resembling in parts coagu¬ 
lated albumin; the capsule of the lens was white and thickened, and the 
lens-substance itself was white, opaque, and in places closely adherent to 
the capsule. 


Foerster, who first called our attention to massage as a means of ripen¬ 
ing cataract, appears to have thought at first that it only hastened the 
degeneration of lens-fibres in cases where the cataract had already com¬ 
menced. Both Hess and Schirmer have shown us, by means of experi¬ 
ments on animals, its effect on normal lenses. The latter opened the 
anterior chamber, and, without making any iridectomy, rubbed the lens 
through the cornea with a strabismus-hook. By thi&^rfradure out of 
fifty-two trials he produced more or less opacity fortujjp’’ times, while in 
six cases he was unable to detect anv lenticular ckO^e. Slight rubbing 
produced a fine radial striation of the superficialities, which increased in 
size and intensity for a few hours until it o<^A*ed a space corresponding 
to the dilated pupil. This cleared up tom c^rfiain extent, but never com¬ 
pletely, and three months afterwards pi^entecl the same appearance it had 
in the second week. There were alsoQ^eper-lying opacities, which caused 
the anterior sectors of the lens to b^^me unduly visible. In ten cases total 
cataract followed, and he founrjQkat this could always be produced by 
prolonged rubbing (from to four minutes). Sections of the lens 

examined by the micro "showed swelling of the cells of the anterior 
capsular epithelium wSt4^ acuo l es iu their protoplasm and nucleus, with 
gradual death and d^jntegration of the latter. The lens-fibres themselves 
became granular /TfiKslightly swollen, with separation of their club-shaped 
extremities ftrd^Jne capsule, the resulting space being filled with granular 
material. were also deeper-lying spindle-shaped spaces between the 

fibres filfed with a similar material. Fig. 62 gives a reproduction of a 
phot^rTyi$>graph in a case of unripe cataract where, after iridectomy, the 


er 1 Von Ammon, Annales d’Oculistique, xxvii. p. 41. 



author made gentle pressure with a tortoise-shell spoon on the lens-capsule. 
The capsule remained intact, and, while the partially opaque lens clouded 
rapidly, there was no inflammatory reaction. Six weeks later the cataract 
was extracted, and the capsule, after it was gently divided by a cystitome, 
was left behind in the eye. The figure represents a portion of the lens 
adjoining the anterior capsule, and shows that such treatment is sufficient to 
make rents in the softened cortical of incipient cataract, while the amount 
of granular degeneration along the fissures shows that it could not be due 
to the cut of the cystitome. The rent here represented runs off obliquely 
through the lens-fibres, and on each side, more markedly at the upper 
margin, the fibres are pulled out of place and their frayed and broken ends 
turned inward, while irregular cavities have formed between them, and the 
fibres themselves are undergoing a granular degeneration much greater 
than those in their vicinity which have not been disturbed by the pressure. 
From this fissure in the lens spaces lead off, running between the fibres, 
filled (as in many other cataractous lenses) with a granular albuminoid 


In simple senile cataract the rate of progression is very slow, and months 
and often years elapse between the period of commencement and that of 
maturity. This is not only true of the form which begins in the periph¬ 
eral cortical layers, but also of that which commences with perinuclear 
opacity; indeed, this latter form, which often occurs in myopic eyes, is 
generally held to be unusually long in ripening. On tlte other hand, 
traumatic and complicate cataracts often form with gre^tfGipjdity. Thus, 
Ritter 1 reports a case where normal vision was lost an^jF almost complete 
cataract was formed in the course of a week, while^t^r&chberg 2 records the 
maturation of cataract in twenty-five days. ^S^eV* describes a cataract 
where there was good vision in March, follo^^fey a ripe cataract in May. 
According to Just, 3 a mother observed a <^n^m*g of the lens coming on in 
her young child during a convulsion, *£^d m another case the eight-weeks- 
old child of a woman whose two pi^lous children had congenital cata¬ 
ract had its lenses cloud in a few^^nutes. Two hours later Just saw the 
child, whose eyes he had pre^jKly examined and found to have clear 
media, and saw that in oneA^Cnem was a mature cataract and in the other 
commencing opacity offihQphs. Carter 4 reports a case of a girl seventeen 
years of age in whortditaract developed in fourteen days, and another 
where in an ansejug^md amenorrhoeic patient it became complete in three 
weeks. The rapwVmaturation of cataract in eyes where it has previously 
existed is mo^CSommon. Nettleship relates an instance where marked 

e rapmV] 

_ __ _.aore common. Nettleship __ 

cataract ^sted in the fellow-eye for sixteen y 

ears, while in the useful 

**ARitter, Klinische Monatsblatter fur Augenheilkunde, 1870, viii. 56. 

^irschberg, Nagel, Jahresbericht, 1874, S. 255. 

^ 3 Just, Centralblatt fur prakt. Augenheilkunde, Januar, 1880, S. 8-11. 

4 Carter, Lancet, 1881, p. 419. 




$> V 

eye a comparatively clear space in the lower outer portion of the lens 
allowed the patient to read his letters and the newspapers, but the ability 
thus to use his eye was lost within three weeks. 



Diminution of Renal Permeability in Cataract Cases .—Frenkel has re¬ 
cently experimented on this subject by injecting methyl blue into the muscles 
of the thigh of cataract patients, and claims that the elimination by the 
kidneys is slower in them than in persons of equal age not so affected. If 
elimination was normal in promptness the cataractous patient was found 
to have diabetes or a cataract due to local eye disease such as iridochorioiditis. 

Deutschmann has directed our attention to the ratio of the occurrence 
of albuminuria in cases of senile cataract , and has classified certain cases 
as nephritic cataract. He found albumin in thirty-three per cent, of his 
cataract cases. His conclusions, however, as to a special variety of cata¬ 
ract which can be so classified do not seem to be supported by more ex¬ 
tended investigations, and there is probably no distinctive nephritic cataract 
except in so far as extensive and long-continued kidney disease impairs the 
general nutrition and thus favors the formation of cataract. Ewetsky 1 has 
added largely to our knowledge of this subject by his careful examinations 
conducted at the Moscow eye clinic and almshouses. Out of two hundred 
cases at the eye clinic thirty-eight, or nineteen per cent., had at times small 
quantities of albumin in their urine, while casts were foil lad in fourteen 
cases, seven per cent. On the other hand, an examinat^Co^ ninety cases 
of renal disease showed retinitis in fifteen per cent, a^^races of cataract 
in 7.7 per cent. In the poorhouse, out of five Iqp^ed and eighty-four 
inmates between fifty and ninety years of age tvfjjmndred and sixty-four, 
forty-five per cent., had traces of cataract.^Of these the urine of five 
' hundred and sixty-one cases was examinecLaM^n fifty-nine, 10.5 percent., 
albumin was found, while in nine, oi^d.Gper cent., casts were present. 
This would look as if in a large pro^^non of cases the albumin present 
was due to prostatitis, cystitis, an^Wther* common maladies of old people. 
Becker 2 in 1888 tells us tha£<(JyShe cataract patients at the Heidelberg 
clinic six per cent, had albi^AUn the urine. Some years since I examined 
over one hundred cases of tfjSraght’s disease in general hospitals, the better to 
study the forms and fiWi^Bncy of albuminuric retinitis, finding twenty-five 
per cent, affected ^vj^kit, while in many of the advanced cases of the disease 
slight opacities lens were present, mostlv as peripheral striae. 


Foerstevin bis valuable essay on the relation between eye-diseases and 
gen^ra^Aseases, has told us that, while in many instances diabetic cataract 

1 Ewetsky, quoted in Nagel, Jahresbericht, 1887, S. 386. 

3 0. Becker, Die Universitaets Augenklinik in Heidelberg, 1888, S. 58. 



develops like senile cataract, in the young it often assumes a different type, 
distinguished by a milkiness immediately under the capsule, with marked 
differentiation between the sectors of the lens. Becker, however, has shown 
that in many cases the incipient opacity lies deeper, with a clear layer in 
front of it, while Horner speaks of the frequent occurrence of punctate 
and posterior cortical cataract in diabetics. Becker, however, in outlining 
the appearance of diabetic cataract, says that cloudiness commences in the 
equatorial zone, spreads thence to the posterior cortical, and afterwards in¬ 
volves the anterior cortical. The opacity usually forms first in the super¬ 
ficial cortical fibres, thus differing from the cloudiness of the cortical which 
occurs in senile cataract with nuclear sclerosis. This is soon followed by a 
rapid and considerable swelling of the lens caused by the endosmosis of 
watery fluid into the capsular sac. The latter author has given us one of 
the most instructive investigations as to the exact nature of diabetic cataract 
in the young. The lens was taken from a patient nineteen years old, who 
died of diabetic coma two days after the performance of a preparatory 
iridectomy. The epithelium of the anterior capsule is well preserved, and 
the equatorial lens-fibres are less affected than those between them and the 
nucleus, where there are numerous more or less spindle-shaped spaces be¬ 
tween the fibres, while smaller ones are visible in the nucleus. Between 
the anterior capsule and the anterior surface of the lens is a large space 
filled with coagulated albuminous fluid, and a similar one between the pos¬ 
terior surface of the lens and the posterior capsule. Becker sums it up by 
calling it an oedema of the lens. As to the frequency with^Ahich cataract 
occurs in diabetics, the same author tells us that out of undred cat¬ 

aract cases operated at Heidelberg, one per cent. had^2fe ar 111 the urine. 
Chemical analysis shows that in many instances thsff\i^ sugar in the lens 
as well as in the aqueous humor. Deutschman* objected to this being 
considered the cause of cataract, because in exrfewments on animals a much 
larger percentage seems to be necessary to ferojlufce opacity; but the experi¬ 
ments usually spread over only a short ^ne, and there does not appear to 
be any reason why extremely minute {yjhntities acting over a long period 
of time should not also produce fact, the cataract of experimental 

diabetes is always produced ra&^ljA while clinical observation shows that 
diabetic cataract usually foftM^owly. It is doubtful, therefore, whether 
the anatomical changes in the early stages of diabetic cataract are 

exactly those found in artificially produced. 

Seegen has repctfisd two cases of spontaneous absorption of diabetic 
cataract, while jmjKah ill has reported a similar one. Koenig 1 has also 
observed a pleiffSig up of diabetic cataract where in one eye in the course 
of two ye^^^sion improved from counting fingers to V. = 1/3. Jn the 
fellow-e^ ctense opacity still remained, but it was less than at the previous 
examipu%n. The same author has also seen a clearing up of cataractous 

Koenig, Societe Ophthal. de Paris, Annales d’Oculistique, Mai, 1897, p. 398. 
aKJ Yol.iV.—21 




opacities in a case of uric acid diathesis, and Despagnet mentioned a resump¬ 
tion of transparency in an arthritic cataract under the influence of Con- 
trexeville waters (observation of Debout d’Estries). Appenzeller records a 
sharp attack of diabetes lasting fifteen days, when there was an acquired 
myopia of 1 D. which disappeared with the diabetes, while Risley has 
reported two cases of sudden transient increase in the refraction of the eye, 
corresponding with marked increase of sugar in the urine, with subsidence 
to normal refraction when the sugar diminished. 


While it has long been taken for granted that atheroma and degeneration 
of the blood-vessels of the eye would, by impaired nutrition of the lens, 
lead to the formation of cataract, Michel 1 has claimed that atheroma of the 
carotids stands in close relation to the occurrence of senile cataract, and that 
one-sided cataract, where the cause is unknown, finds in this condition a 
satisfactory explanation. Karwat, 2 following up this suggestion, gives 
twenty cases, in only three of which was there no degeneration of the 
carotids. Van Brommel 3 maintains similar views, and Nickelsburg 4 
states, where atheroma affects the carotid of one side only, that cataract 
usually develops first in the corresponding eye, while, when it affects 
equally both carotids, both eyes are simultaneously affected. Weil, 5 how¬ 
ever, after careful examination of fifty-three individuals with cataract, 
found only sixteen affected with atheroma of the carotids, while in thirty- 
seven no such affection could be demonstrated. In si^Vof the sixteen 
cases in which atheroma was demonstrated, the disease ^^ha artery was on 
the same side as the first-developed cataract, whik ^he other ten the 
reverse w^as the case. Weil calls attention to t®Vnnpossibility, even in 
emaciated people, of determining the state internal carotid by pal¬ 

pation, and to the difficulty of doing j)Aihe common and external 
carotid. Knies also maintains the contrary view, and has often by careful 
palpation demonstrated that the gre^fer development of the atheroma of 
the carotids was on the side on wIflg!. cataract had not developed. My 
own experience would indicate : % atheromatous arteries are quite com¬ 
mon in patients with catan^Vbnt that while atheroma of the radials is 
frequent in patients witft^^taract, and a similar state of the temporal 
artery not uncommon* dJJ^rom a of the carotid of sufficient extent to be 
detected by palpation\g>rare, and it seems doubtful whether its presence is 

1 Michel, Dasfyymalten des Auges bei Stoerungen im Circulations gebiete der Carotis, 
Festschrift zu jfflbgn Prof. Horner, 1881. 

2 Karwjv^kitrage zur Erkrankung des Auges bei Carotis Atherom, Inaug. Diss., 
W urzburg!^&e3. 

3 Brommel, Zur Etiologie der Cat. Senilis, Inaug. Diss , Wurzburg, 1889. 
^f^jic£elsburg, Weitere Beitrage zur Etiologie der Cataracta Senilis, Inaug. Diss., 

ISfrirzmirg, 1892. 

5 Weil, quoted by Becker, Anat. der gesunden und kranken Linse, 1883, S. 128. 



of any value in the prognosis of cataract except as a possible indication 
of diseased conditions of the walls of the intra-ocular vessels. 


The more one examines the eyes of elderly people the more one is struck 
with the extreme frequency with which some degree of opacity of the lens 
is found,—so much so that one is almost inclined to agree with the famous 
dictum of Walt her, “that- every one becomes cataractous who does not die 
prematurely.” On the other hand, in only a very small percentage of these 
cases does the cataract ever advance far enough to prevent useful employ¬ 
ment of the eyes. Of those who have the lens opacity sufficiently developed 
to cause their complaint to be entered in the books of an eye hospital as 
cases of incipient cataract, we find in various clinics a percentage varying 
from 5 per cent, to 10 per cent. Thus, Dor 1 out of 8008 cases gives 8f per 
cent, of lenticular opacity. Knapp, out of 10,004 cases in Europe, gives 
7.6 per cent., while in New York, out of 6379 cases, he finds but 5.5 per 
cent. Wecker 2 gives 12 per cent, as the number occurring at his clinic. 
Rydel, 3 in Cracow, reports 7.65 as the proportion, while Cohn’s statistics 
give 6 per cent. Schoen 4 out of 6689 eyes of all ages examined for len¬ 
ticular opacity gives 18.4 per cent, as having greater or less degrees of cata¬ 
ract. Of these cases a very small proportion are mature cataract. Thus, 
if the number of extractions represents, as it nearly does, the number of 
ripe cataracts at the Wills Hospital, we have in twenty years, from 1872 to 
1891 inclusive, 129,806 cases of eye-disease and 1428 extractions, making 
1.1 per cent, of mature cataract; while if the later years, where the num¬ 
ber of patients is much larger, are taken, we have a still/sSrailer percentage. 
Thus, in the five years from 1886 to 1891 inclusiv&«Q«fjave 53,453 cases 
of diseases of the eye and 488 extractions, a percrfMge of 0.9. To make 
this absolutely fair the congenital and infantihOwtaracts which were dis¬ 
ci nded should be added, and in the twent/ya^ there were 205 of these, 
giving the percentage of congenital and fnfatmle cataract as 0.01. 


While, as previously stated, c^JfWact often comes on without demonstra¬ 
ble cause, either local or gen<^S£foevertheless it is certainly influenced by 
the general health, coming /ftO?arlier when the nutrition is impaired, espe¬ 
cially in those cases wh^reitne lowered vitality has produced local changes 
and degenerations *ii£iJie blood-vessels of the uveal tract. According to 
Arlt, out of 882 patients between the ages of twenty-six and eighty- 

two, 626 were i&'t^een forty-five and seventy years of age. It is, I think, 
the genera^^^rience that it is more frequent and develops earlier in farm- 

,^^)r, Nagel, Jahresberiekt, 1837, S. 319. 

J We 

recker and Landolt, Traite Complet d’Opktalmologie, vol. i. p. 847. 
; Rydel, Klinische Monatsblatter fur Augenheilkunde, 1879, S. 90-94. 

■ Schoen, Funktions Krankheiten des Auges, 1893, S. 158. 




ers and day laborers than it does in those classes of society who are less ex¬ 
posed to exhausting physical labor and to intense glare and heat. Accord¬ 
ing to Hirschberg, there are many more cataracts ripe in the farming class 
at fifty years than are to be found in city dwellers at the same age. He 
also tells us that climate with exposure to light and heat have much to do 
with it, either from direct action on the eye or by the state of nutrition in¬ 
duced by high heat, severe manual labor, and scanty nutriment, and that in 
the East Indies the majority of cataract patients come to operation at forty 
years or thereabouts, while in Europe the majority of extractions are at 
sixty-two 3 ears Of age. Jackson found that out of 1545 patients at the 
Wills Eye Hospital at Philadelphia over fifty years of age, 449 had some 
lens opacity. Arranged in five-year periods the percentages showing such 
opacities were as follows: 15 per cent, between fifty and fifty-five, 16.1 per 
cent, between fifty-five and sixty, 30.2 per cent, between sixty and sixty- 
five, while in the ten-year period between sixty-five and seventy-five he 
found 77 per cent. 


This form of keratitis is of not infrequent occurrence and has long been 
familiar to clinicians. It is not, however, peculiar to cataract operations, but 
is found also in inflammatory affections of the cornea. Raehlmaun 1 gives an 
excellent description of it, both as occurring after linear operation for cata¬ 
ract and in rodent ulcer. When present, it develops after closure of the 
wound, and consists of grayish stripes situated in the dee^r layers of the 
cornea and running at right angles to the direction of t^%jv%md. At times 
these are joined by cross-lines, making an irregular work. There have 
been but few pathological examinations of such op™^fes recorded. Becker 2 
found in one case swelling of the deeper layeijj i ( 0 th a massing of lymphoid 
cells in the enlarged interstices of th e_ti 4 §yy Laqueur and Reckling¬ 
hausen 3 found a hyaline degeneration (AhS protoplasmic elements with 
secondary distention of the lymph-pJfcages. According to Mellinger , 4 the 
use of cocaine causes swelling of tl) 0 ip s of the corneal wound with some 
shedding of the epithelium, ver a striated keratitis, while sublimate 

solutions constantly cause keratitis, due to cloudy swelling of the 

corneal tissue, more esjl^^W^ of the corpuscles and their protoplasmic 
branchings, which b^£ 0 ^^ thicker and more wavy than in normal tissue. 
While it must be coVgijJered demonstrated that the corneal tissue changes 
in striped keratitjj^which have been described by Becker, Recklinghausen, 
and others, re^t^ exist, nevertheless it is difficult, as was pointed out by 
.oQwiuerstand how such minute changes could give rise to the 
^ ^ranees as we find them after cataract operations and in some 



\/ Be< 

_iehlmann, Klinische Monatsblatter, 1877, S. 1-21. 

Jecker, Atlas der pathologischen Topographie des Auges, 1887, Bd. iii. S. 83. 

3 Laqueur and Recklinghausen, Bericht der Heidelborger Congress, 1887, S. 116. 

* Mellinger, Arcbiv fur Ophthalmologie, xxxvii , 4, S. 159. 



corneal ulcers. Nuel 1 was the first to prove that the microscopic appear¬ 
ances are due to the production of ridges in the membrane of Descemet and 
in the immediate underlying layers of corneal tissue. He found that this 
variety of corneal opacity is due to a folding of the cornea (which he attrib¬ 
utes to too tight bandaging), which produces cracks in the posterior corneal 
epithelium (membrane of Descemet) and a subsequent oedema of the corneal 
tissue. The diffuse opacities of the cornea which come on in from two to 
five days after operation he attributes to the use of solutions of sublimate, 
which, according to his view, do not need to be injected into the anterior 
chamber to produce them. More recently Hess 2 has given additional evidence 
in favor of this view by a careful examination of a human eye which had 
been operated on for cataract, as well as by a study of experimental striated 
keratitis in rabbits. Schirmer has since published a paper on the subject, 
in which he pictures the folds of the membrane of Descemet and the imme¬ 
diately underlying corneal layers as occurring in experimental cataract op¬ 
erations on rabbits and in artificially produced hypopyon keratitis, and 
also a similar state of affairs which he found in a wounded human eyeball 
which went on to suppuration in ^ 

a case of hypopyon keratitis. He a \ 

further mentions appearances in 

the corneae of shrinking eyeballs fa p 

which were clinically similar to * y 

tile usual appearances of striated Folds of Descemet's membrane in striated keratitis. 

keratitis, but which lay near the (Hess.) 

ante’" —^ p Jl 1 1 1 41 p 11 






1 Nuel, Congres de la Societe Fran<jaise d’Ophth., May, 1892. 

2 Hess, Arcliiv fur Ophthalmologie, 1892, xxxviii. S. 4. 





In normal cataract operations where the incision is in the corneal tissue 
the lips of the wound lie more or less accurately in apposition, and there 
occurs a felting of the swollen ends of the corneal fibres of one lip with 
those of the other. This is usually most marked in the central layers of 
the cornea, the anterior and posterior layers retracting to a greater extent. 
This felting of the corneal fibres is assisted by a fibrinous exudation, and 
constitutes the first stage of repair, being usually sufficiently complete in 
from twenty-four to forty-eight hours to retain the aqueous humor and thus 
permit its accumulation and the re-establishment of the anterior chamber. 
Within a few hours the anterior epithelium commences to proliferate and 
grows down into the wedge-shaped space between the lips of the wound, 
and by the fourth day has usually filled out th’S space and united with the 
epithelium on the other edge of the wound. By this time a plug of fibrin 
has also formed on the posterior edge of the wound, and the union has thus 
become fairly firm, although still readily burst open by any undue pressure 
of the lids, by coughing, or by any other violence. Later fibrous tissue 
and blood-vessels, shooting in from the periphery, form in the wound, and 
some time between the second and the sixth week cause a firm and perma¬ 
nent union. Even at this latter stage, however, it has by no means attained 
its eventual consistence and strength, and I have known a severe accidental 
blow at this period to burst open the wound and evacuate^ large portion 
of the contents of the eyeball. As is well known clinician, the 

period of repair varies greatly in different cases. and 66 give a 

photographic representation of a section through d^&xtraction wound nine 
weeks after the operation. They show resp()gt^|fy the upper and lover 
halves of the incision. In the upper half a double epithelial plug 

extending inward from the corneal epitfieVtovb that in the peripheral lip 
of the wound reaching much farther^owfi into the wound. Phis plug is 
in the processs of absorption, and i^^tng replaced by fibrous tissue. In 
the lower half of the wound frayed and bent edges of the corneal 
lamellae are united to those <^&e other side of the incision by a newly- 
formed mass of fibrous the wound in the membrane of Descemet 

is covered by a fibrous @Nwhich at its centre is adherent to the hyaloid 
membrane of the vi ^er^ is. It was long believed that the cut edges of the 
membrane of p^emet never reunited, and they probably never do so 
directlv, but and Wagenmann 1 2 have lately shown that the en¬ 

dothelial yett^n the membrane proliferate, and form a thin vitreous mem¬ 
brane ^^Voften in time glues together securely the cut edges. Where 
j%Ls in the sclerotic and there is no conjunctival flap the process of 
is very much like that of a corneal wound, but where a considerable 

1 Gepner, Archiv fur Ophthalmologie, 1890, xxxvi., 2, S. 255. 

2 Wagenmann, ibidem, 1891, xxxvii., 2, S. 21. 

Fig. 65. 

Upper half of extraction cicatrix nine weeks old. (Photographed by Dr. George W. Norris.) 

Fig. 66. 

r half of extraction cicatrix nine weeks old. (Photographed by Dr. George W. Norris.) 

Fig. 68. 

Displacement of lips of the wound, with cystoid cicatrix. 

Fig. 69. 

Cicatrix after sclerotomy. 



flap exists an epithelial plug forms only at the point where the divided con¬ 
junctiva unites, and the closure of the wound is mainly due to effusion of 
lymph and felting of the ends of the cut scleral fibres. Where there is 
any considerable gaping of scleral wounds Lubiusky 1 has shown that 
the healing is mainly due to the subconjunctival and chorioidal tissues, 
which form an intercalated plug. Where any foreign substance comes 
to lie between the edges of a cataract incision, such as remnants of lens- 
matter, a portion of the iris, a tongue of capsule, or a loop of vitreous, the 
firm and permanent healing is always delayed, and on any pressure on the 
eyeball or rise of intra-ocular tension there is a slight leakage of aqueous, 
separating the superficial fibres, and often laying the foundation either for 
a filtration cicatrix or for a staphylomatous projection. 


This varies very much in different cases even where the healing is clin¬ 
ically a normal one. In some few instances the lips of the wound after 
complete cicatrization are almost in their original position, separated only by 
a thin layer of cicatricial tissue, but in most instances the distal lip over¬ 
rides the proximal to a greater or less extent, and this with pull of subse¬ 
quent cicatrization produces a flattening of the cornea in a meridian at right 
angles to the incision. The intra-ocular pressure has also a tendency to 
cause an increase in the curvature of the horizontal meridian. 


Fig. 57, at page 311, from Becker, shows a wound in^£h4 cornea from 

Pig. 67. 


cataract operation; riding up of peripheral lip of the wound. (Becker.) 

flap exjjs^tion which has healed in a nearly normal position, while Fig. 
67*Trop the same author, shows an upriding of the lower lip of the 


1 Lubinsky, Archiv fur Ophthalmologie, 1867, xiii., 2, S. 377. 

_ : ___ 



wound. Fig. 68, taken from one of my cases of glaucoma, exhibits a 

slight displacement of the flap and a projection of the proximal end into 

the anterior chamber. It is also a good example of cystoid cicatrix. The 
iris has prolapsed into the wound, and has prevented almost entirely any 
union of the corneal tissue, the closure having been effected mainly by 
the epithelial plug, with slight amount of fibrous tissue uniting the sub- 
epithelial layers of the cornea. In contrast with these methods of healing, 
Fig. 69 shows the dense cicatrix of a sclerotomy in the corneo-scleral 
junction, but at the same time its great effect in loosening up the adjacent 
fibres of scleral tissue. Fig. 70, which gives a less magnified view of 
the section previously shown in Figs. 65 and 66, affords an entire view 
of the line of incision, and shows well the characteristic displacement 
of the distal lip of the wound. 


Since Jaeger, in 1868, first demonstrated the true nature of zonular 
cataract it has been a favorite subject of study by ophthalmologists, and 
large numbers of cases have been reported, with a careful description of 
the appearances as seen by the use of the ophthalmoscope and oblique light. 
It is, however, only within the last few years that, by the careful study of 
thin sections of such lenses, our knowledge of the pathological changes has 
advanced beyond the statements given us by Jaeger. To Deutschmann, 
Beselin, Lawford, Schirmer, Hess, Peters, and E. Treacher Collins we are 
indebted for careful microscopic examinations of this form of cataract. 
Deutschmann 1 found a double layer of opacity env^^iig an intact 
nucleus, and covered in turn by clear cortical, the>&fwling being ap¬ 
parently due to finely granular detritus collected i^tssures between the 
fibres. Beselin 2 and Lawford 3 obtained simila^^ilts, except that they 
both observed more or less degeneration of t&Jrfucleus. Schirmer, 4 who 
had an opportunity of investigating six <vf§$sJ^iought that the main cause 
of the opacity was innumerable smaji ctets and vacuoles which existed 
everywhere around the periphery of(cSS nucleus. Both the nucleus and 
the cortical contained also opacities ol less extent and not sufficient to 
make them appear cloudy eitheiQrni oblique light or the ophthalmoscope. 
There was but little sepai^i^o^r the layers of the lens-fibres from each 
other. In one of these cpeVthere was also well-marked anterior capsular 
cataract. Hess 5 consjoei^lme true perinuclear opacity as caused by small, 
irregularly round vacuoles, whose equatorial diameter varied from 0.002 
to 0.01 millii *nd thinks that the angular or rafter-like opacities at 

the equator 4 o mcleus are caused also by vacuoles. In a case where 

1 Deutschmann, Archiv fur Ophthalmologie, xxxii., 2, S. 295. 

2 Beselin, Archiv f. Augenheilkunde, xviii., S. 71-86. 

3 Lawford, R. L. O. H. Rep., vol. xii., 2, p. 184. 

4 Schirmer, Archiv fur Ophthalmologie, xxxv., 3, S. 147. 

5 Hess, ibidem, xxxix., 1, S. 183. 

Fig. 70. 


hotographed by Dr. George W. Norris.) 



punctate cataract was coexistent with zonular, he found club-shaped and 
irregularly-ovoid opacities between the lens-fibres, and to them he attributes 
the punctate dots. The arrangement of the minute dots in this instance 
corresponded with the distribution of the lens-fibres, and not with the 
intersectorial spaces. Peters gives drawings of a case where in one eye 
the central part of the nucleus has fallen out in the preparation, and where 
in both there is enormous separation of the nucleus from the cortical layers 
by large, irregularly-shaped cavities filled with fluid. According to Col¬ 
lins, who has examined microscopically seven zonular cataracts, the patho¬ 
logical changes are of three sorts: first, fissures between the lens-fibres 
which run concentrically with the nucleus, and which may or may not be 
filled with granular material; second, small vacuoles, of an average size 
of 0.005 millimetre, filled with hyaline material; third, larger spaces, 
averaging 0.02 millimetre in diameter, filled with granular material. 
These, he considers, correspond to the radiating spokes. In one of the 
seven cases the nucleus was entirely clear. In the remaining six there 
were vacuoles in it. In two these were distributed pretty evenly through¬ 
out the nucleus. 

Fig. 71 was taken from a case in my own practice. The lens was 
extracted from a man, aged thirty-five, with zonular cataract, in whose 
family cataract was hereditary, and whose twelve-year-old niece was at 
the same time under my care for zonular cataracts on which I had per¬ 
formed discissions. The plate is a reproduction of a photomicrograph, and 
shows that the nucleus of the lens exhibits small, irregularjArounded dots 
of degeneration, some of these dots being filled with Ji^apular material, 
while others have bright, highly-refracting content&A^at minute spots, 
filled with granular material, are the cause of the pjffVuclear opacity; that 
the cortical fibres adjacent to the nucleus are^yJy clear, although they 
exhibit slight, irregularly-rounded spots^Q^^^generation, and that the 
whole mass is moderately coherent, with ^mylmle formation of cracks or 
cavities between the lens-fibres, those nq&r the posterior surface being evi¬ 
dently artificial and due to the drag o£/the cutting microtome. Between 
the peripheral fibres may also be^egu in many places elongated masses of 
granular material. These arqJk^ciently numerous to form an outer, 
although incomplete, zone >^7Pacity. The nucleus itself is irregular in 
shape, and, instead of beiiQbvoid, is irregularly prominent at its posterior 
surface, while the adjoining lens-fibres show a similar angular curve. At 
the summit of thkCSw-ve, as well as at the equator of the nucleus, both 
above and below^jere is a mass of granular opaque material. The layers 
of lens-fibr.^^^mediately surrounding the nucleus are comparatively 
healthy, ^^^Ri^Doth in the anterior and posterior cortical they are more 
granular\ and are separated in many places by granular albuminous 
mat&jjltCjA somewhat higher magnification shows in the nucleus of 
tli^Oens evidences of a similar but less marked degeneration, — viz., 
tfWmte, irregularly-rounded areas of disintegration, some of which are 



filled with granular material, while others have contents of a high re¬ 
fracting power. Figs. 72 and 73 show, slightly more magnified, the 
appearances of the opaque band of a zonular cataract extracted from 
another patient. There is much less granular material in it than in the 
first case, and many more drops of a highly-refracting clear material of 
various sizes. We thus have the opportunity of examining what is prob¬ 
ably the same process in different stages. In the earlier stage the material 
in the affected zone, viewed with a low power, looks granular, but, ex¬ 
amined with an immersion-lens, it proves to be composed of round masses, 
of which the material is cloudy and finely granular, while towards the 
outer edge and scattered through it are nucleated cells in process of degen¬ 
eration, possibly remnants of imperfectly-formed epithelial cells thrown off 
by the capsular epithelium at the time at which it was in contact with the 
diseased zone and before the comparatively healthy external layer had 
formed. In the second specimen we have a more advanced stage of the 
process. No distinct cells with cell nucleus are to be seen, but we have 
rounded spaces filled with some highly refractive oily material. The fact 

that there may be in the same lens a 
FtG ' 4- double, or even a triple zone of opacity, 

Fig. 72 

Section of a zonular cataract showing equator of the zonule. 

(Photographed by Dr. George W. Norris.) 

Fig. 73. 

Section of a zonular cataract showing equator of the zonule.—More highly magnified. 

(Photographed by Dr. George W. Norris.) 



torial diameter of the lens of a child of ten to eleven months is 7.46 milli¬ 
metres, which Jaeger gives as the measurement of the lens of the newly- 
born. If, as seems fair to assume, we suppose that some disturbance of 
lenticular nutrition occurs at an early stage of foetal life while the direction 
of the lens-fibres is axial; that we may have cloudiness of them and some 
form of axial cataract; that when concentric fibres are added to the lens a 
like disturbance might give us a nuclear cataract, while a little later after a 
clear nucleus had once been formed similar nutritive disturbance would give 
us the usual one-zoned band of opacity; similar disturbances of nutrition 
occurring even after birth in the superficial layers of the lens where the 
epithelium is constantly producing new fibres would produce the larger 
zones of seven to eight millimetres, and there might still be vital force 
enough in the epithelium under better conditions of nutrition to wrap them 
in a layer of healthy and transparent fibres. Foerster has long ago called 
our attention to the similarity of the process of the formation of perinuclear 
cataract to that of zonular, and I myself had an opportunity of seeing a 
finely granular double zone of opacity form in the lens of a patient sixty 
years of age, where the accompanying swelling of the lens produced con¬ 
siderable myopia, as is detailed in a subsequent section under the head of 
Second Sight. The only essential difference between the formation of such 
layers in foetal life and early childhood and those occurring later seems to 
be that in the one case the epithelium possesses enough vital force to form, 
under improved nutrition, an overlying layer of healthy fibres, while in the 
other the germ force is not sufficient to do so, and we soorujjave the forma¬ 
tion of other varieties of opacity in other parts of theX&^s} The theory 
that convulsions would cause such violent crampA^0fhe ciliary and lid 
muscles as to produce a sort of massage of the wft; newly-formed lens- 
fibres against the comparatively hard nucleu^^^ neld by Arlt, Horner, 
Schoen, and others, looks plausible, and tlm^tNmiittence of the convulsions 
might on this theory be held to corresp^ruj) to multiple layers of opacity 
in the lens ; but while the frequent o^forrence of convulsions in rhachitic 
children is everywhere admitted, thewiAxmsiderable number ought to pro¬ 
duce either more frequent layersd^pacity or total cataract. According to 
v. Arx, out of one hundred a«q^e|ghty-nine cases of zonular cataract, one 
hundred and seven, or 50^^per cent., had been subject to convulsions, 
and 5.9 per cent, had^wo^^ir cataract in both eyes. Certain it is that the 
most careful inquiry 
cases fails to eliejj 
more extended ^ 

cases of zq^^Scataract are certainly congenital. 


'the history of patients in the large proportion of 
iehCiyy evidence of previous convulsions or spasms, and a 
^5^tnination shows that a very large proportion of the 

cataract may be either congenital or acquired by pathological 
^cesses started by ulceration of the cornea or injury to the capsule (Knies, 
er). As was mentioned in discussing the formation of zonular cataract, 



Fig. 75. 

it is probable that-a disturbance of the nutrition of the lens in early foetal life, 
while the lens-fibres run in an axial direction, may cause it. When there is 
a combination of anterior polar and zonular cataract Knies and Leber think 
that the newly-formed transparent fibres are hindered from joining by the 
adhesion in the axial line between the two cataractous zones, and consequently 
the anterior polar opacities will gradually diminish in size, and there will 
be only a thread running back to the zonular opacity. Hess, owing to ex¬ 
amination of the chicken embryo, is of the opinion that axial cataract is 
due to delayed union of the mouth of the lenticular sac, and that all the 
then formed fibres become more or less opaque, especially the strands run¬ 
ning from the nucleus to the 
point where the sac has finally 
closed. Bach reports an axial 
cataract occurring in the lens of 
a medium-sized and apparently 
healthy rabbit. The opaque 
band ran from an anterior cap¬ 
sular cataract to a thicker part 
in the nucleus, and was thence 
continued by a thread to the 
posterior pole of the lens, where 
it again broadened out. The 
opaque band consisted of degen¬ 
erated lens-fibres with fine black 
pigment in places, and at the sides quantities of small vs^tOes and myelin 
masses. Fig. 75 shows a nuclear cataract of a rabbit opaque bands 
running to the anterior and posterior poles (after B^pjS 

Axial cataract. (Bach) 



I. Congenital Cataract and the dQlaract of Infancy.—There is nat¬ 
urally some difficulty in drawing th^ine between congenital cataracts and 
those forming during adolescence^^ it is comparatively rarely that newly- 
born children are examined^tfMLe ophthalmoscope, and except where the 
cataract is so marked a^4c^jrract immediate attention the eyes are not ex¬ 
amined until it become^^dent during adolescence that the acuity of vision 
is less than normal^ at this period it is difficult to prove that the opacity 
of the lens has notftEVeloped after birth. Enough cases have, however, been 
observed, andH^sooservation in some instances substantiated by autopsies, 
to prove th^t^tCfe varieties of lens opacities enumerated under this head are 
usually prenatal in their incipiency, and due to disease of the foetus or to 
its fa^^^Qevelopment. 

irr ^Axial Cataract.—In this form we have an opacity extending in the 
ion of the antero-posterior axis of the lens which may go completely 



through it or may occupy only a portion of the axis. A cataract of this 
variety is often irregularly spindle-shaped, and may exist alone or be 
accompanied by opacities in other parts of the lens. If the opacity be 
dense and the rest of the lens clear there may be tolerable vision, although 
Knies 1 has shown how much it interferes with the change of shape of the 
lens under the influence of the ciliary muscle, and diminishes the range 
of accommodation. A somewhat similar form of opacity may at times be 
developed after birth, and it is then usually accompanied by central cap¬ 
sular cataract. Axial cataracts probably date from that early period of 
development of the lens at which, the lens vehicle having closed, long 
straight cells push forward from the posterior capsule to meet the growing 
cylindrical epithelium from the inner surface of the anterior capsule, or, as 
Hess suggests, and as has been stated with more detail in the section on 
pathology, may be due to abnormal delay in the closure of the lens sac. 
In cases undoubtedly congenital it has been found associated with zonular, 
with anterior polar, with posterior polar, and with central cataract. 

III. Congenital Anterior and Posterior Polar Cataract. — Congeni¬ 
tal anterior polar cataract is probably of two varieties, one due to an adhe¬ 
rence between the pupillary membrane and capsule, F ^ 

the other due to foetal inflammation, a plug of lymph 
having been deposited on the latter. Figs. 39 and 40, 
at page 301, give a good example of the former variety, 
while Fig. 76 (after Wilde) is a characteristic picture 
of the latter. In either case the tissue adherent to the K j ilU 

outer surface of the anterior capsule goes on to became 
atrophic and thinner, but it interferes with the nutritioif^i 



and left a concavity in the posterior layer of the lens. Von Ammon 1 has 
demonstrated a similar state of affairs in the rabbit, and H. Muller 2 in the 
goat. This form of cataract is very distinct from the stellate form, occur¬ 
ring also at the posterior pole where the opacity is seated in the layers of the 
posterior cortical. These latter forms are at times observed at birth and 
in early life, and are symptoms of preceding retinal or chorioidal disease. 
In later life they are apt to occur in cases of typical pigment degeneration 
of the retina and in many other varieties of chorio-retinal disease. 

IV. Zonular Cataract.—By far the most frequent form of partial 
congenital cataract is that known as zonular cataract, where a clear or par¬ 
tially cloudy nucleus is enveloped in a layer of opaque and cataractous lens- 
fibres, which are again covered by a clear and apparently normal cortical. 
Sometimes two or three such opaque zones can be demonstrated, each sepa¬ 
rated from the underlying one by a layer of transparent fibres. In such 
cases, if the opacity is slight and thin and the superficial clear layers of the 
lens have sufficient depth, the pupil looks normal, and it is only when the 
patient complains of dim vision, and we examine the eye with the ophthal¬ 
moscope or oblique light, that the cataract is discovered. Von Jaeger 3 was 
the first to give a correct description of this variety of cataract, and to con¬ 
firm it by an examination of the extracted lens. He describes it as a uni¬ 
form gray opacity of a single layer of lens-tissue enveloping a clear nucleus 
and covered by a layer of clear cortical. He had observed it “ seven times 
in four individuals.” The equatorial diameter of the hazy zone varied in 
the different cases from three to five millimetres. A year kter Graefe tells 
us that this is the most common form of cataract in cl^ldlk|pd. Arlt had 
previously described it as stationary nuclear cataract, Realizing the cleai 
centre. The equatorial edge of the opacity may bemther smooth and round, 
or may send out opaque striae towards the equafftfe of the lens. With the 
ophthalmoscope we may differentiate it frotfivhuclear cataract by the fact 
that the opacity seems clearer in the cent re ^nd denser in the periphery, 

fcwliere the opaque layers of the an- 
Q terior and posterior parts of the lens 
approach each other, while in nu¬ 
clear cataract the opacity is of course 
denser at its centre. Zonular cata¬ 
ract may occur without other len¬ 
ticular opacities, but is at times 
a ; companied by greater or less de¬ 
velopment of axial cataract. The 
peripheraH^dFJ^of the opacity may be smooth and rounded, or it may send 
off radshoots into the later-formed peripheral layers of clear cor¬ 
tical. 77 reproduces the instructive but diagrammatic drawing from 

1 Von Ammon, Archiv fur Ophtlialmologie, iv., 1, Taf. 5. 

2 H. Muller, Gesammelte Schriften, S. 286. 

3 Yon Jaeger, Staar und Staar Operationen, 1854, S. 17. 

Some forms of 


aract. (Liebreich.) 



Liebreich. In the first drawing we have a section of an ordinary single¬ 
layered zonular cataract, in the second a complete zone of opacity with axial 
cataract and a partially formed second zone, in the third there are double 
zones, and in the fourth a poorly developed small lens with a single zone. 
Fig. 78 (after Spicer x ) gives a careful drawing of a zonular cataract with 
some axial opacity, as seen with dilated pupil and oblique light; the space 
between the inner edge of the pupil and the outer edge of the diseased por¬ 
tion of the lens consists of clear fibres, except where the radiating white 
lines intrude upon it from the periphery of the cataractous zone. In Fig. 79 

Fig, 78. Tig. 79. 

Right eye. Left eye. 

Zonular cataract. (Spicer.) 

Triple and double zonular cataracts. (Hess.) 

(after Hess * 1 2 ) are reproduced the mixed zonular and axial cataracts of a 
woman both of whose children also had congenital cataract. In the right 
eye we have the representation of a triple zonular cataract and in the left a 
double one. In each eye the opaque radiating striae are narrow and pointed 
towards the pole and broad at their peripheral ends. In <^te&case also the 
fact that the position of the margin of the lens cairJ^^dlstinctly seen 
through the iridectomy coloboma shows that it waystpailer than normal. 

Fig. 80. 

Zonular cataract with clear central axis. (Heinzel.) 

Zonular cataract with curved^ 
projections into the clear^le^Mib- 
stance. (Jessop.) 

At times, in^a^of these peripheral radiating fine striae, we have curved 

conical pr^^^ons into the clear lens-substance, the apex of the cone point- 
mg to fh\ centre of the cataract, those in the anterior cortical having the 

rv V -—- 1 

1 Spicer, Trans. Ophth. Soc. U. K., 1892, vol. xii. p. 108. 

2 Hess, Archiv fur Ophthalmologie, xxxix., 1, S. 182-220. 



convexity forward, while those behind the opaque zone have their con¬ 
cavity forward, as is well shown in Fig. 80 (after Jessop 1 ). Such are 
the more usual appearances of zonular cataract, but recently Heinzel 2 has 
described and pictured a case from Fuchs’s clinic where there is a zonular 
cataract with a clear central axis, as is represented in Fig. 81. According 
to Purtscher, 3 zonular cataract existed in the upper half of each lens only 
in a case where there were anterior polar cataract and retained pupillary 
membrane; there was also interstitial keratitis. 

Zonular cataract is often hereditary, but it is the tendency to the for¬ 
mation of cataract rather than the special form of it which is transmitted, 
and we find at times other forms of cataract develop in other members 
of the same family. In the vast majority of cases zonular cataract is 
developed in both eyes and the opaque zone in each eye is of the same 
diameter. E. v. Jaeger noticed a case where it was monocular, and accord¬ 
ing to D. E. Mueller 4 we may have in the same individual well-developed 
zonular cataract on one side with a shrunken cataract (C. arida-siliquata) or 
even posterior polar cataract on the other. In most instances there is no 
complication in the shape of atrophy of the optic nerve or disease of the 
retina or chorioid, and in cases where these are excluded the acuity of vision 
will vary with the density of the cataract and with the extent to which it 
covers the pupillary space. In many instances it is sufficient to enable 
those affected by it, after correction of their astigmatism, to read coarse 
print with a magnifying glass, and to perform various kinds of manual 
labor which do not call for accurate eye-sight. When dilatation of the 
pupil materially betters the acuity of vision, the patip^A^ often much 
benefited by the performance of a small iridector^. I have known 
zonular cataracts to remain unaltered many years, J^GKoften as the patients 
grow older there is an increase in the opacitw/flithe lens and at times a 
development of senile cataract, as is well showron the case of Leber, 5 where 
in typical zonular cataract, six years aft|r Mi^ffirst examination, there was 
clouding of the entire lens. In otherfoisnmces the progress of the opacity 
is very slow, as is well shown in th^^Tlowing case. B. T. was first seen 
by me in 1871 in his twenty-sixth ^ar. He had in each eye a single-layered 
zonular cataract measuring as ^ffas could be determined by the ophthal¬ 
moscope five millimetres, ^A^hfed that he had had defective vision all his 
life. The eyes were sliglifl^myopic. V. in each without a glass = 20/CC. 
With —1/360—l/2^C^Taxis 135°, Y. = 20/L in O. D.; and in O. S., 
with the same gl^* axis of Cy. at 45° V. =20/LXX. He wore these 
glasses for distaare^But preferred to read without a glass. Twenty-six years 
later the pafi^fc^had become more myopic, and even with a suitable correc- 

1 W^^^essop, Ophth. Soc. U. K., vol. vii. p. 171. 

2 *iainzel, Deutschmann, Beitrage zur Augenheilkunde, Heft v. S. 27. 

^CT^imscher, Centralblatt fur prakt. Augenheilkunde, February, 1894, S. 33- 

4 D. E. Mueller, Archiv fur Ophthalmologie, ii., 2, S. 166-178. 

W 5 T .f 


1 Leber, ibidem, xxvi., 1, S. 295. 



tion vision had become much impaired. The patient stated that this had 

occurred in the last few years. O. D. —1/7 combined with —1/24 Cy. axis 
135°, V. == 20/CC. O. S. —1/7 combined with —1/24 axis 45° V. = 5/CC. 
The opacities in the lens have become more dense,-but the myopia is proba¬ 
bly axile, as with dilated pupil a large conus can be seen to the outside of 
each disk, and in the left eye there were several small spots of chorioidal 
atrophy in the macular region as well as above and below it. 

Zonular cataract may exist in individuals with no marked deviation 
from general health, but is more frequent in the feeble, poorly-developed, 
and rhachitic. In the latter class of cases there is frequently also rhachitic 
deformation of the skull, but more commonly, as Horner has taught us, a 
coincident development of rhachitic teeth. The central incisors are usually 
the most affected and present curious irregularities in the distribution of 
their covering of enamel, and at times in their conformation. The enamel 
in normal teeth shows a series of fine transverse, almost microscopic ridges, 
which by reflection of light give the tooth its brilliantly white surface. In 
rhachitic teeth these ridges are irregularly developed and very much more 
prominent, with correspondingly wider depressions between them. At the 
neck of the tooth the enamel, instead of dying out gradually on the roots, 
ends often with a marked ridge, while the labial and palatine layers of the 
enamel, instead of making a smooth, even surface at their junction, cause 
irregular ridges at their point of meeting. According to V. Arx, out of 
one hundred and eighty-nine cases of zonular cataract sixty-six per cent. 

lio/l r>Vi onlnfin foo+V> T f moo of Ann +imn 

. , , , gT -t .... ziuiiuiar utuuruut. 

it is due to the cramps oftlje ciliary mus- 

cle. Horner also anc^many subsequent writers report convulsions during 
,r "a large percentage of the cases of zonular cataract 

1 Wecker et Landolt, Traite d’Ophthalmologie, vol. ii. p. 904. 

1 Wecker et Landolt, Traite d’Ophthalmologie, vol. ii. p. 904. 

e^^Tndeed, until Becker published his case, where the 
^as observed by the parents immediately after birth, and 
■ely examined the eyes in the thirteenth week, there was no 



Fig. 83. 

reports a case where in a nine-year-old child at first examination there was 
well-marked zonular cataract in one eye with an absolutely clear lens in the 
other. A few months later zonular cataract developed in the sound eye. 
Graefe reports three cases in which he satisfied himself that zonular cataract 
developed in previously clear lenses dislocated into the vitreous. Zonular 
cataract has also been caused in adolescence in consequence of an inflam¬ 
mation due to a perforation of the cornea. Such cases, if it were not for the 
well-known diagnostic acumen of their reporters, would lead us naturally to